Belichick and Special Olympics athlete James Coffey waved the Bruins' banner in front of a raucous crowd at TD Garden before Wednesday's game against the St. Louis Blues.
The team is fighting for its seventh Stanley Cup and lead the best-of-seven series 1-0. Belichick, considered one of the greatest NFL coaches of all time, joins a long list of Patriots that have shown love for their Boston brethren on ice.
Retired tight end Rob Gronkowski, wide receiver Julian Edelman and cornerback David Andrews have all been named fan banner captains this season, WBZ-FM sports radio Boston reported.
Members of the 2011 Bruins teams that took home the franchise's most recent Stanley Cup were banner captains in Game 1 win.