That's pretty misleading. Our starting CF missed pretty much the entire season, our 2B will miss 1/2 the season, our 1B will miss about a 1/3 of the season, Ortiz is old and was getting a lot of time off because of his cold streak to start the season, and even some backups missed time.
The real competition JD had was a catcher who hit the DL for a time, an aging slugger who got benched a bit, SS, 3B, and backups.
On top of that, he hasn't exactly been that good this season. .344 OBP, .794 OPS...
With Youk, Pedroia, (and Vmart for a while) gone, he needed to step up his game... he hasn't. In Fact, he's regressed from June, with August being his worst month this season (.300 OBP, .698 OPS). Don't sugar coat it, with the team needing him desperately, he's completely disappearing.