Adam Dunn is closing in on his fifth straight 40-home run season. John Sommers/Icon SMI

Adam Dunn, Reds

The subject of more trade rumors than that Colombia bill, Dunn remains a Red just a few short months from free agency. His perceived value isn't great -- J.P. Ricciardi's opinions are shared by a number of people within the game -- but few players bring the bat that Dunn does, and his defense has improved to the point where he's not giving back half the runs he creates. He hasn't been as productive as Bradley or Bay, but he's been more consistent at a high level, and is therefore a better bet to sustain his performance.

The Diamondbacks have a number of reasons to pursue Dunn. He's a free agent at the season, so they won't have a commitment that blocks Eric Byrnes' contract.

With Chris Young and Justin Upton they have a good outfield defense, enabling them to mix in Dunn. (Given that Conor Jackson has been playing left, Dunn may well be an upgrade.) They have the kind of midlevel depth in prospects that could be used to acquire a rental.

Oh, yeah, and their offense has been awful, and they desperately need Dunn's bat. His low-contact approach doesn't make him the best fit, as they could use a .315/.360/.470 guy who hits doubles, but his .388 OBP from the left side would be a godsend for a team reaching base at a .323 clip. Inserting Dunn into this lineup would add 20 runs to the team total, re-establish the D'backs as the team to beat in the NL West and help assure that the division winner finishes above .500.

Justin Duchscherer, Athletics

Sure, why not? If Beane can deal Rich Harden at the peak of his market value, can the AL's ERA leader be far behind?

Duchscherer will simply not be better than he was in the first half, when he benefited from some exceptional defense behind him to post an ERA below 2.00.

An effective reliever before becoming a starter this season, Duchscherer is likely to see some performance degradation as he passes innings markers he hasn't approached since he was a prospect back in 2003. He would be in line for a massive raise in arbitration, and will be a free agent after 2009. All things considered, there are more reasons to deal him than to keep him.

Because he doesn't have a high strikeout rate, the best fits for Duchscherer are contenders with strong defenses and weak rotations. The Braves, third in the majors in Defensive Efficiency, have supported Tim Hudson and Jair Jurrjens well, and both are similar in type to Duchscherer. Charlie Morton has been rushed to the majors and is averaging 6.5 runs per nine innings and five innings per start. If Tom Glavine gets healthy, he might be better than that, but I wouldn't bet on it. A very conservative estimate for Duchscherer down the stretch is six innings a start with a 3.75 RA. Adding Duchscherer would save the Braves at least 20 runs, and that's being conservative. The back of the Braves' rotation is just that bad; Duke could be worth 25-30 runs, up to three wins, if he keeps pitching as well as he has.

As mentioned above, the Braves have three top prospects and some depth behind that. The A's have been trading for quantity; if that trend continues, the Braves could work something out. If the A's shift gears and focus on Hanson or Schafer -- I can't see Heyward being dealt -- that will make things harder. The Braves are in a very tough spot, likely to lose Mark Teixeira and watching a career year from Chipper Jones, but also owning a relatively young core that makes planning for the future a good idea. It's not impossible to play for now and the future at the same time, but most trade partners -- especially good ones -- force you to choose.

Matt Holliday, Rockies

Unlike a number of the players above, Holliday's perceived value is extremely high, as he's coming off a near-MVP season and a homer in the All-Star Game. Holliday is a complete player who hits for average and power and plays solid defense in left field, good enough that he routinely plays right in the Midsummer Classic. The Rockies are looking for a monster package for Holliday, who won't reach free agency until after 2009.

Just about every contender can use a player of Holliday's caliber. The ones with the greatest needs are probably the teams covered above, the Braves and Diamondbacks, along with the two New York squads. Getting Holliday will require at least one top-tier prospect, however; for the Braves that means Schafer or Heyward; for the Mets, Fernando Martinez. The Diamondbacks might have to include Max Scherzer. For this reason it is unlikely that Holliday will be traded over the next couple of weeks. That caliber of prospect rarely changes hands any more, which is one reason why Matt LaPorta being dealt in the Sabathia trade was such big news.

Any of these teams would gain three wins with Holliday replacing their left fielder, or in some cases, their right fielder. Holliday's home/road splits have drawn some attention, but those are a poor way to evaluate a player. It's information, just potentially misleading. Holliday would be a productive hitter anywhere, and his defense would be worth five to 10 runs over many of the players he'd be replacing. That's both a good reason to trade for him and a good reason for the Rockies to ask for the moon. Unless the Mets elect to move Fernando Martinez, or the Cardinals put Colby Rasmus into a deal, I don't think Holliday goes anywhere.

Brian Roberts, Orioles

Roberts was strongly rumored to become a Cub for most of the off-season. The Orioles refused to move him, and seem unlikely to do so now, as they have him under contract through next year. That's shortsighted, because a staggering number of contenders could use a leadoff or No. 2 hitter.

Foremost among them is the White Sox, who have gotten a reasonable .344 OBP from their leadoff hitters but just .302 from the No. 2 spot. While Alexei Ramirez has turned heads at second base, his seven walks this season are an execrable total, and leave him with a .312 average and a .332 OBP.

Roberts isn't just an upgrade -- he's one of the top 10 players in the AL, with a .294 EqA and plus defense at second base. A team with the power core the White Sox have needs high OBPs batting in front of it, so while the numbers say that Roberts would add 15-20 runs as compared to Ramirez, plus a few on defense, the real-world results would be a little better than that.

The White Sox have a terrible farm system, which would make it hard for them to pry Roberts away from a reluctant Orioles team. Still, he may be the one player on the market who makes enough of a difference to them to pursue. Three years ago a lack of OBP atop the lineup nearly killed them in August and September; they're being chased by teams good enough that they should try to avoid a similar problem this year.

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