Not necessarily.
Think about it. He had an absolutely outstanding, phenomenal year last year.
Outside of that, though? He has 21 HR in 380 games. So, was last year the Joe Mauer year for him? Or is he a perennial 20+ HR guy? Not to mention that he has suffered 2 major injuries in the past 3 years. I'm not saying he's injury prone because I don't think he is. But, that's something that could well be held against him in contract negotiations.
I'm not saying anything is certain, but it will be interesting to see if the Sox offer him a 7 year/105-112mm (15-16mm AAV) deal. If so, I'm not real sure that he could get better elsewhere unless he throws up another 25+ HR season next season, assuming the Sox don't extend him.