The Nats’ 7-4 victory over Philadelphia on Tuesday night had to be the most satisfying win of the season. Not only did the Nationals rack up a badly needed victory (coming off a two-of-three series in New York), but the team finally seemed to be doing everything right. While Tuesday night’s hero was Jayson Werth (who went 2-3, scored two and put a Joe Blanton offering in the left field seats), there were plenty of other reasons for celebrating: the savvy Livan Hernandez confounded Phillie hitters for nearly seven innings, Wilson Ramos (2-3, two RBIs, and a dinger of his own) solidified bragging rights for being one of the best young players in the game, and (once again) the Nats defense was flawless.

But it was Werth who led the way, and there’s now little question that he, with Ryan Zimmerman, is emerging as a team leader. “Obviously, anytime you hit a home run, you are going to have some satisfaction,” he said after the game. “Was it extra special against those guys? Probably a little bit. I was trying to perform well for Charlie [Manuel]. He hasn’t seen me play in a while. It was a big win.” The Nats are now back at .500, a perfect symbol of their solid play. They play the Phillies again tonight, but this time they’ll be facing Roy Halladay. It’ll be the toughest test of their young season.

If there’s one thing that’s absolutely useless, it’s the MLB “Power Rankings” — a weekly “metric” (a word used to describe everything except comprehensive empirical data), that compares a team to the other 29 in baseball. ESPN’s rankings combine run differential with a team’s place in the standings, XLOG ranks teams by a measures of “net runs” (runs scored minus runs scored against), while the Chicago Tribune’s Phil Rogers just ranks teams — using no particular “metric.” In this week’s ESPN rankings the Nationals are 28th (behind the Rays, Red Sox, Tigers and Twins), in XLOG the Nats are 21st (which makes more sense) and in the Rogers this-is-just-how-I-feel ranking they are a woeful 27th.

So where are the Nats — really? The most useful rankings are notionally statistical, and straightforward: the Nationals rank 8th in runs scored (in the NL), 8th in OBP, 15th in hits, and 15th in batting average. That seems to confirm what Nats fans feel: the Nats line-up has been particularly anemic in the season’s first two weeks, but the hitting has been timely. The Nats are also right in the middle of the pack in pitching stats: 10th in ERA, 7th in strike outs, though a surprising fifth in BAA. But Washington is much better than average in fielding and (though this is much harder to measure), has relied on their more-than-solid bullpen to hold leads.

Phil Rogers has this right: the best stats remain the standings, the feel you have for a team — and some sense of the unseen intangibles. So if Nats fans were to make an objective assessment (which means they have to put aside their customary negativity), they’d have to say that the Nats are right where they should be, at .500. There are some good signs: the Nats are much better defensively than they were last year and have a top-flight bullpen. Their starting pitching is actually not that bad. They’re better than the Mets and match-up pretty well with the Marlins (though the Fish have better starters). They’re a middle of the pack team with a lot of potential. This early judgment vindicates Mike Rizzo, whose off-season move emphasizing defense has yielded solid results.

That’s all good news, especially considering where the Nats were last year — which was near the bottom in nearly everything. The bad news is that to rise above the pack the team will need to stay healthy. That’s a problem, particularly considering Ryan Zimmerman’s stint on the DL and Adam LaRoche’s tweaky shoulder. Can the Nats get better? Sure they can. But they’re going to have to rely on good performances from those fill-in veterans that Rizzo brought aboard as super subs in the off season. They’re going to have to hit and field for Zimmerman and LaRoche. Those are big shoes to fill.

The trade for Chicago lefty Tom Gorzelanny, the signing of ex-Brewers fist clenching righty bulwark Todd Coffey and the surprise recruitment of uber utilityman Jerry Hairston, Jr. may well have concluded the Nationals’ off-season moves, though Nats’ GM Mike Rizzo refuses to say he’s done. Even so: the Nats, were they to conclude now, have significantly improved the club, though that front-of-the-rotation ace they looked for remains elusive. Gorzelanny, for all of his steady talents, isn’t it. Gorzelanny is solid, to be sure, but his 7-9 record in Chicago is less a reflection of the North Side Drama Queen’s 2010 troubles than of Gorzelanny’s sometimes iffy performances. The lefty can go through terrible spells of leaving his fastball up in the zone, as attested to by his troubled 2009 season, when he never seemed to hit his rhythm.

Still . . . still, Gorzelanny provides innings and steadiness — 136 last year and 201 in 2007, his best year. And “Gorzo” (as his Chicago followers called him) seems immune (knock on wood) to the kinds of nagging injuries that have plagued Washington pitchers: he took two back-through-the-box line drives last year in Chicago and kept on soldiering. He seems also “a good clubhouse man,” which is a premium for Rizzo & Co., who want to add players who want to play: Gorzelanny was relegated to the bullpen in Chicago last year, but with nary a whimper. But it says something about Washington’s pitching staff that Gorzo arrives here as one of the team’s solid starters and a near sure-bet to be number two or three in the rotation. Considering what’s left in the market his acquisition is a good move, and Washington didn’t have to give up a lot to get him.

Mike Rizzo has added five pieces to the club in the off-season: the steady-as-she-goes Gorzelanny, bells and whistles big-bat outfield czar Jayson Werth, nice-glove-nice-guy first sacker Adam LaRoche, utilityman Hairston and (now) bullpen workhorse Todd Coffey. Of the five, the acquisition of Coffey is the one under-the-radar acquisition that could pay unlikely and unpredicted dividends. Like Gorzelanny, Coffee doesn’t seem likely to set the team on fire (62 innings, 4.76 ERA), but he has good stuff and a solid presence that will put pressure on an already-good bullpen to get better. The one thing that Coffey brings is a firebrand in-your-face presence that includes an up-and-in fastball that is particularly effective against plate-crowders. He’ll be fun to watch. Oh — and then there’s the trade of Josh Willingham for upside prospect Corey Brown and potential closer Henry Rodriguez; the deal ranks as a “potential steal,” but only if Rodriguez can lasso his upper-90s fastball and become the team’s closer-of-the-future.

What does it all mean? In the end, while Mike Rizzo couldn’t get his ace, the team that will arrive in Florida in a month or so is better than the 2010 version, though how much better remains to be seen. Our guess? Over the moon fans say the Nats might make a run at a Wild Card, but it’s more likely the Half Street Nine would do well to flirt with .500.

Jim Riggleman & Company have a lot to think about over the next few months, not the least of which is how to improve the Nats sloppy defense — first in the majors in errors — and what to do with Adam Dunn. The two are closely related, particularly given the questions being raised about Dunn’s prowess at first base. Ben Goessling (in “The Goessling Game“), focused on Dunn’s defense in his latest blog, noting that the Nationals “have made no secret of the fact that Dunn’s defense is the main thing they’re still evaluating when deciding whether to give the 30-year-old a contract extension.” But Goesseling praises Dunn for making the successful switch to first base, implying that his defensive play has been one of the surprises of the year: “To Dunn’s credit, he’s improved markedly at first base this season, becoming a slightly below-average fielder instead of an anemic one,” Goessling writes.

Goessling isn’t the only one praising Dunn. Over at SI, Joe Sheehan provides a list of players who are among the worst defensive players in the game (Yuniesky Betancourt, Brad Hawpe, Hanley Ramirez, Andre Eithier and Ryan Braun), while noting that Dunn “has adapted well” to being moved from the outfield to first base “showing good hands if limited range.” Dunn’s successful shift is unusual, Sheehan writes: “It’s rare that a player can move to first base and increase his value, but Dunn has done so.” So if Goessling and Sheehan are impressed with Dunn — and if the big guy from Texas is ripping the cover off the ball (and he is) — what’s the problem? Well, the problem seems to be Friday night in Philadelphia, when Dunn’s lack of range hurt him in getting to a ball stroked down the right field line and where the big man’s size limited his stretch to snag a ball thrown by Ian Desmond. The Goessling-Sheehan notes on Dunn are now the subject of some attention on the web (as MLB Trade Rumors runs through the Nats’ first base options) and increased questions over the utility of “defensive stats.”

So  . . . how concerned should the Nats be with Adam Dunn’s defense? Dunn has made seven errors in 116 games playing first for the Nats, a statistic that actually reflects the common judgment that Dunn is a below average first baseman. Derrick Lee has made six errors (in 106 games), while Joey Votto has just four in 112 games. Lee and Votto ought to be considered the class of the league (Lee is tall, agile with lots of range; Votto is young and tough with great leaping ability), but the best in baseball (at least according to this single, and admittedly limited, “errors and chances” measure) might well be Friars’ first sacker Adrian Gonzalez who seems to have everything — agility, range, height and experience. Gonzalez has just five errors in 118 games, and he’s there, day-in and day-out. Which is not to mention Albert Pujols (with just three errors), who has everything that Gonzalez has (but perhaps not as much agility), or James Loney (a Gonzalez without the range, it seems to me) — with an astonishingly nearly perfect three errors in 122 games.

So the critics are right: Adam Dunn is an average to below-average first baseman: he ranks below Derrick Lee, Joey Votto, Adrian Gonzalez and James Loney, is on a par with Atlanta’s gimpy and aging Troy Glaus, but is a ton better than either Arizona’s Adam LaRoche (10 errors in 112 games) or Philadelphia’s Ryan Howard — whose defensive gaffes are legendary (11 errors in 101 games). The problem with all of this is that defensive stats don’t really tell us a lot, which is why Sabermetricians have struggled to come up with better ways of measuring defensive prowess. But, as Tim Marchman noted recently, the statistical models are controversial, contradictory, and often fly in the face of common sense. In truth, it’s nearly impossible to compare Dunn’s defense to Pujols’ or Loney’s or anyone elses, because only Dunn offers a glove to Ian Desmond — whose lack of experience regularly (viz. Friday night in Philly), makes Dunn look like Adam LaRoche (whose own shortstop, Stephen Drew, throws baseballs as naturally as the rest of us eat chicken).

That’s not to say that fans of Adam Dunn should ignore his defensive woes, or refuse to admit them. It’s only to note that, when it comes to Dunn (and anyone else playing in the field), defensive stats will either only confirm what we already know (do we really need a raft of stats to tell us that Adam Dunn lacks range, experience and agility), or will stand as a confusing single data point in an overall picture (Colin Wyers over at Baseball Prospectus points this out, and pretty convincingly). Which leads us back to where we started — with this single question: do Adam Dunn’s offensive stats (his home run, OBP and RBI totals) compensate enough for his defensive woes to make Riggleman and Rizzo think about signing him for a few more years? The answer, as always, depends on the option — of whether Dunn’s prospective replacement will improve the Nats defense so markedly that they can live without the 40 or so home runs that the Texan will hit.

Ben Goessling says that the Nats are thinking along these lines, by considering Carlos Pena as a useful replacement for Dunn at first. Pena has the same kind of pop (39 home runs last year, 46 in 2007), and while he’s more experienced and more agile at first, it’s hard to argue that he’s actually better defensively (10 errors in 133 games in 2009). Perhaps more importantly, it’s hard to argue that Pena’s more resilent. The savvy Tampa first sacker sat out most of 2005 and nearly all of 2006 with injuries, is known to be plagued by an inexplicable June injury bug — and has been hit with broken fingers, pulled hamstrings and swollen foots. And Adam Dunn? The last time that Adam Dunn had any kind of injury at all (knock wood, right now, and knock it hard) was 2003. Over the course of the last seven seasons, Dunn has played in (count ‘em) 161, 160, 160, 152, 158, 158 and 159 games. That’s the real stat, the one that matters. In comparison, in that same stretch, Carlos Pena played in 131, 142, 79, 18 (18!), 148, 139 and 135 games. Nearly a full season less. Maybe Pena is better at first. Maybe. But it’s hard to make an error when you’re sitting on the bench.

So if all of this is true, what’s all the hubbub about Adam Dunn? And why, now, are we suddenly hearing about Carlos Pena? The answer might be that the Nats really do want to get better defensively — and they think the way to do that is to replace their 40 homers a year guy with a player (like Pena) with a puzzling history of nagging injuries. Or maybe, just maybe, all of the complaints about Dunn’s fielding have nothing to do with his defense at all. After all, there seems to be a trend here, and it has more to do with the bottom line than booted balls — and should be perceptible to anyone who pays close attention: when the Washington Nationals’ front office starts talking about replacing Dunn’s below-average glove at first base, what they’re really talking about is replacing his big salary in the accountant’s book.