SI’s Jon Heyman has weighed in with a detailed look at what MLB ballclubs need as teams assess their mid-summer runs. A lot of this is guesswork and some of it likely to be wrong (who would have thought that the Pirates would trade Nate McLouth for a bunch of no-names), but some of Heyman’s speculations sound about right. Heyman says the Nats are gaining the attention of teams in need of hitting to keep them in a pennant race or to replace a suddenly injured star. The Red Sox are a clear example. “The Nation” is worried that David Ortiz’s struggles at the plate are permanent. Eventually, they’ll have to admit that, and search for a bat to fill his place in the line-up. That list could include Nick Johnson, Adam Dunn and Josh Willingham. “The Nation” has a handful of impressive young arms to offer in return, including Justin Masterson and Michael Bowden. Sadly, the one “can’t miss” pitcher that a lot of teams want — Clay Buchholz – is probably untouchable.

What is notable about Heyman’s post, however, is not his speculation on Johnson, Dunn or Willingham — it’s his silence on Austin Kearns, who continues his career-long slump at the plate. You have to believe that the Nats would much sooner give up Kearns than part with Josh “The Hammer” Willingham, who is not only a Kearns-like good citizen, but who’s recent turns at the plate are as close as the Nats can come to a power surge. Willingham has started to resemble the Ryan Zimmerman of two weeks past: he’s seeing the ball well, hitting it hard and putting it over the fence. To put this as plainly (and uncomfortably), as possible: the reason that Kearns won’t get traded is not because the Nats don’t want to give him up (they do), but because other teams don’t want him. That’s not true for Willingham.

But then, who wouldn’t want Willingham? The hammer’s 30, healthy, hits for power and plays hard. There’s an argument to be made that his size and abilities have been consistently underrated — both here, and when he was with the Marlins. He has nine home runs this year in only 111 at bats. There’s no reason to believe that he would hit as well over a 162 game (and 600 AB) stretch, but he can easily outpower Kearns and he’s a more discriminating hitter than Dukes. Both the Red Sox and Cardinals — who now say they’re also in the market for a hitter — would likely choose Willingham over Dunn, whose big bucks contract and concrete glove out-muscle his obvious power.

Nick Johnson is a different story. When he’s healthy he can hit, has a longer history than Willingham, plays first base better than Dunn, and is known for being intensely competitive. With the apparent injury of Detroit first baseman Miguel Cabrera (who pulled up lame in the game against the Red Sox), Johnson is just the kind of ballplayer “the Motor City Kitties” will need to claw their way into the post-season. The Leyland’s can’t possibly believe that Jeff Larish is the answer at first when Johnson – a near-Gold Glove and consistent hitter – is available. The Bengals might even be willing to give the Nats one of their young arms in return: someone like (say) Ryan Perry, a former first round pick with a high-90s fastball. The Tigers have bullpen arms to give: Perry, Joel Zumaya (they won’t part with him), Brandon Lyon, Fernando Rodney (they won’t part with him either), and Bobby Seay. That’s five relievers. The Nats have one: Ron Villone.

Agreed: you’d have to think long and hard before you’d give up a 22-year-old who’s pitching like “the terminator” for an oft-injured first baseman, but if Cabrera’s limp is (as rumored) a pulled hamstring, then Detroit GM Dave Dombrowski might have little choice. And if that turns out to be the case (it’s all speculation, after all), interim Nats GM Frank “just pull the trigger” Rizzo should make the trade. Then too, dealing Johnson would clear up a lot of issues: it would put Adam Dunn back at first base (where he belongs) and return “Kentucky” to right field, where he could show off those legendary defensive skills – the skills he loses when he plays center. It would also mean that the Nats could keep Willingham. Fine by me. Sometimes, it’s the trades you don’t make that end up being important.