By R.J. Anderson //

Nearly 50 games into the regular season and Derek Jeter does not look like Derek Jeter. It starts with his .275/.319/.399 slash line, which looks like it belongs to Jeter’s backup in any given year. Jeter is walking in fewer than 5% of his plate appearances – a career low – and striking out more than in recent years. Is there any upside to keeping the Yankees’ captain, or is this the beginning of the end?

Jeter is seeing significantly fewer pitches than normal. Between 2005 and 2009, Jeter’s seasonal low for pitches per plate appearance was 3.72, this year it’s 3.59. Making matters worse is that Jeter is hitting nearly 70% of his batted balls on the ground. Given the limitations of batted ball data – i.e. whether the ball is being hit hard, or softly – it’s impossible to say whether Jeter is replicating his trademark out (the slow grounder to shortstop) more often than usual. Two things are certain: 1) Jeter’s .300 BABIP is well below recent norms and 2) Jeter is swinging outside of the zone more than he ever has before. That could be a sign of pressing or a sign that Jeter’s plate approach is waning.

While Jeter should not be expected to continue to perform this poorly heading forward, the reality is that he is a soon-to-be 36-year-old shortstop. Mike Axisa of the wonderful River Avenue Blues site recently tweeted that only three 36-year-old shortstops in the last 50 years have posted an OPS+ of 100 or better. Those three were Barry Larkin, Ozzie Smith, and Luis Aparicio, three of the all-time positional greats.

Deciding whether to sell low on Jeter or not might be the most difficult decision some fantasy owners will make this season. Simply put, there’s no right answer. Yes, he’s old for a starting major league shortstop. But he’s also coming off a fantastic season and is one of the finest talents to ever take the field. The best news might come from 2008. Jeter had similarly poor outings in April and May — posting OPS of .654 and .715 respectively – before hitting his stride and finishing as an above-average hitter. That was just two seasons ago, so it’s certainly not impossible to think Jeter could do it once more.

For more on Derek Jeter and other struggling veterans, check out Bloomberg Sports’ Fantasy Tools.