Last July, a pair of notable second basemen exchanged hands in trades. Omar Infante was acquired by the Tigers (along with Anibal Sanchez) for Jacob Turner, Rob Brantly, Brian Flynn and a swap of competitive balance draft picks. Infante didn't hit much in 2012, but he remained under control for 2013 and has been worth 2.4 wins above replacement (per Fangraphs) this season alone.
More famously, Marco Scutaro was acquired by the Giants in exchange for Charlie Culberson. Scutaro's Herculean .362/.385/.473 batting line down the stretch helped propel the Giants to the playoffs where he won NLCS MVP honors by hitting .500 over the course of the seven-game series.
Here's a look at some keystone players who could be on the move in 2013…
Starters
Chase Utley (Phillies), Daniel Murphy (Mets), Rickie Weeks (Brewers), Gordon Beckham (White Sox), Darwin Barney (Cubs), Mark Ellis (Dodgers)
Utley, with his .279/.348/.510 batting line and plus defense, is the prize of the crop. However, there's no guarantee that the Phillies will part with a player who has long been one of the faces of the franchise. Any offer will need to exceed the value of a compensatory draft pick, as the Phillies will surely make a qualifying offer to Utley after the season given his play thus far.
Murphy is once again enjoying an under-the-radar season. The 28-year-old has been a league average hitter according to both OPS+ and wRC+ (each is an even 100) to go along with solid defense and good baserunning. He's hit .296/.336/.417 over the past three seasons and looks headed for double-digit totals in homers and steals in 2013. With two years of team control remaining, the price tag would be high.
Weeks got off to another brutally slow start, but he's hitting .316/.385/.571 with six homers since May 22. He's owed $11MM in 2014 with an $11.5MM option for 2015, and another three weeks of strong offensive play could grab a contender's attention. Milwaukee GM Doug Melvin could help his case by including some cash in a trade.
Beckham missed almost two months with a broken hamate bone this season, but he's hit well when on the field (.331/.360/.424). He's not hitting for power or walking though, so the primary source of his production has been a .384 BABIP that's exactly 100 points higher than his career mark. Because he's controlled through 2015, the Sox won't part with the former No. 8 overall pick cheaply, but they're reportedly listening to offers anyone other than Chris Sale and Paul Konerko. A career .250/.315/.384 hitter, Beckham hasn't lived up to expectations and could be a "change of scenery" trade candidate.
Barney doesn't hit much, but only Dustin Pedroia has graded out as a better defender at second (according to both UZR and The Fielding Bible) since the start of the 2011 season. He's not yet arbitration-eligible, so the Cubs would likely ask for a lot, but given their full rebuild, it'd make sense for them to listen.
Ellis is a free agent after the season, and even if the Dodgers position themselves as buyers, they could look to move him and pursue an upgrade. He's hitting .267/.310/.359. Others may not view him as a starter, but he's a reasonably competent bat with a strong defensive track record.
Backups
Nick Punto (Dodgers), Kevin Frandsen (Phillies), Cliff Pennington (D-Backs), Skip Schumaker (Dodgers), Jamey Carroll (Twins)
Punto, Pennington and Carroll all profile as glove-first acquisitions, though Punto has had a decent season with the bat (.260/.328/.320). Carroll hasn't hit much, but his batted-ball profile hasn't worsened from last season's solid offensive performance. A .259 BABIP has kept his overall production down, but even if that corrects itself, he'll never hit for power. Pennington has a $3.25MM guaranteed salary in 2014 and is arb-eligble for 2015, while Punto is a free agent after the season and Carroll has a $2MM vesting option for 2014 that triggers at 401 plate appearances.
Frandsen has been hitting well this year and has been particularly tough on left-handed pitching (.310/.429/.552). He's not a good defender, but he has MLB experience at all four infield positions and has even seen a little time in the outfield. He's arbitration-eligible for a second time this winter.
Schumaker hasn't done anything with the bat this season nor is he regarded as a good defender. The Dodgers would likely be happy just to shed his modest salary and open a roster spot. He could be a candidate to be designated for assignment if they do make an upgrade.
Other Possibilities
Danny Espinosa (Nationals), Ryan Roberts (Rays)
There haven't been strong indications that the Nats would part with the struggling Espinosa, but Anthony Rendon has hit well at second base since taking over after Espinosa's struggles and wrist injury. Teams could try to pluck Espinosa away from Washington, though the asking price would likely be steep, as he was viewed as a core player just a couple months ago. He did draw some trade speculation in late June.
Roberts was optioned to Triple-A Durham on Tuesday and doesn't seem to have a spot on the Rays' current roster. He hit .250/.303/.402 in 142 plate appearances this season and is regarded as a solid defender at both second base and third base.
For more on the 2013 trade market, check out Tim Dierkes' analysis of the trade market for catchers and the trade market for first basemen.