He is most well known for his gaffe on an onside kick in the 2014 NFC Championship game that allowed the Seattle Seahawks to make a late fourth-quarter comeback and defeat the Packers.

On December 15 against Dallas, Bostick suffered a foot injury late in the second half; he was placed on season-ending injured reserve six days later.

[7] In the NFC Championship Game against the Seattle Seahawks on January 18, 2015, with slightly over 2 minutes remaining and the Packers leading 19–14, Bostick, the Packers' third-string tight end, misplayed a Seahawks onside kick by ignoring his blocking assignment and stepping in front of All-Pro receiver Jordy Nelson who was assigned to catch and was waiting for the ball.

The ball bounced off Bostick's helmet and was recovered by Seahawks wide receiver Chris Matthews.

Mason Crosby made a game-tying field goal with 14 seconds left, but Seattle won 28–22 in overtime.

Bostick was widely credited in both Wisconsin and National sports media as having made a Bill Buckner type mistake costing his team a chance for a championship.

[8][9] In his postgame interview, Bostick acknowledged that he was supposed to block so that Jordy Nelson could recover the onside kick.