That was the smart play in that situation.
The play was 4th and 14 at NE 35, the pass was intercepted by Arrington at the NE 20, and returned to the NE 30. If the pass is incomplete, the Pats get the ball at their own 35 instead of their own 30. Besides getting a first down, or a reception between the NE 30 and 20 (Turnover on downs), this was maybe the third best outcome of this play, where throwing the ball out of bounds or grounding it would have been boneheaded. 90% of the time when you draw up a play like that on 4th down, you force the issue down the field.