In his second season as a big-leaguer, Valencia was struck by the infamous sophomore slump, with his OPS sinking by 122 points after an outstanding rookie campaign. That drop-off, however, was largely attributable to a 70-point dive in BABIP, which suggests that with steady peripheral rates and neutral luck his numbers at the plate will creep back upward in 2012.

Yet, judging by Ron Gardenhire's comments during the course of last season, Valencia's offense was not deemed by the club to be his most worrisome deficiency. If the young third baseman's starting job becomes endangered at some point this year, it seems likely that his glove will be the cause rather than his bat.

Late in August, Gardenhire expressed his frustration with Valencia's passive approach at the hot corner. On occasion, the manager intimated through media outlets that the team's future at third base had fallen into question.

You could hardly blame Gardy. After looking surprisingly sharp in the field during his big-league debut, Valencia showed severe regression in Year No. 2. Not only was he far more sloppy, committing 18 errors, but his range was visibly deteriorated. I'm reluctant to apply the UZR metric in single-season samples, but the difference there was stark: after putting up a 10.2 UZR/150 in 2010, Valencia finished at -6.1 in 154 games last season. In other words, UZR showed a 16-run defensive swing from one season to the next.

Whether you buy into that statistic or not, it seems clear that Valencia took a sizable step backward in the field last year, and that if he's unable to reverse that trend, his grip on the starting job will continue to loosen. As we've seen time and time again in the past, Gardenhire and the Twins are far more tolerant of substandard production at the plate than a failure to consistently get the job done defensively.