Biggest Surprise

Adrian Beltre signed a one-year deal last off-season and had an outstanding comeback year. The move from pitcher-friendly Safeco in Seattle to hitter-friendly Fenway in Boston was incredibly kind to the third baseman. Beltre hit 28 HR, the second-highest total in his 13-season career. Beltre also hit .321, the fourth-best mark in the American League.

Biggest Bust

Jacoby Ellsbury entered the season having swiped a combined total of 120 bags in his rookie and sophomore years. In 2010, the outfielder came nowhere close to fulfilling expectations, thanks largely to significant injuries. And when he did play, he wasn’t very productive. In 78 at-bats this season, Ellsbury only hit .192. However, given better health and better fortune on balls hit into play, Ellsbury should be able to bounce back strongly next season.

2011 Keeper Alert

In deeper leagues Jed Lowrie makes an interesting play, since good talent at shortstop is hard to come by these days. In 2010, Lowrie overcame an early injury and performed extremely well after being called up in late July. In 197 plate appearances, Lowrie hit nine home runs and sported a mighty impressive ratio of 25 walks to 25 strikeouts. A former Baseball America top 100 prospect, Lowrie has the upside to be a poor man’s Dustin Pedroia.

2011 Regression Alert

We could point to Beltre’s high BABIP or Ellsbury’s low BABIP, but instead let’s consider health as the key point of future regression. This season, the Red Sox experienced tremendous bad luck on the injury front. The team suffered season-ending injuries to Ellsbury, Pedroia, and Kevin Youkilis — three of the team’s most valuable batters. The misfortunes contributed to Boston’s inability to make the playoffs. Given better health, the Red Sox as a whole may score more runs in 2011, padding batters’ counting stats.

For more on Red Sox hitters, check out Bloomberg Sports’ Fantasy Tools.