The Red Sox have officially reached agreement on a one-year, $750K MLB contract with outfielder Grady Sizemore, reports Rob Bradford of WEEI.com. Sizemore, 31, is represented by CAA Sports. The deal includes significant incentives based on both plate appearances and the number of days Sizemore appears on the Sox roster, Scott Lauber of the Boston Herald reports (Twitter links). Jon Heyman of CBSSports.com reports (Twitter link) that the deal could reach $6MM if all are met.

Once one of the game's brightest stars, Sizemore has not played since 2011 due to a variety of injury issues, including microfracture surgery on his knee as well as operations on his back and a sports hernia. Over the 2005-09 time frame, Sizmore put up an excellent .276/.368/.488 line (with 125 home runs and 128 steals) while playing outstanding center field defense. That made him the fifth most valuable position player in the game over that time, according to Fangraphs, which values him at 28.7 fWAR over that stretch. Over 2010-11, however, Sizemore only saw a total of 435 plate appearances and posted a meager .220/.280/.379 triple-slash.

For a Red Sox team that saw longtime center fielder Jacoby Ellsbury leave via free agency, Sizemore represents an interesting option. Boston had figured to go forward with top prospect Jackie Bradley Jr. as the starter, and the team also controls another player with substantial center field experience in Shane Victorino. But Sizemore brings both depth and upside to the table, and is expected to compete with Bradley for the center field job over the spring, tweets Alex Speier of WEEI.com.

If the Sox decide at some point to give active roster spots to Sizemore and Bradley (both lefties), fellow lefty Mike Carp (already the subject of trade speculation) could end up as trade bait. Of course, given Sizemore's injury history and long layoff — not to mention Bradley's own inexperience — the Sox could wait to see how things play out in Spring Training before making any other moves.