What happened: Former NFL star Rob Gronkowski was spotted repping Buffalo Sabres gear in Buffalo, with the moment shared by SportsCenter on social media. The appearance comes as the Sabres are deep into their second-round playoff series against the Montreal Canadiens. Gronkowski, an Amherst, N.Y. native, has long been a vocal supporter of Buffalo's pro sports teams.

Why it matters: Celebrity endorsements amplify a fan base already energized by the Sabres' first second-round appearance in 19 years. After eliminating the Boston Bruins in six games, Buffalo carries momentum into a Montreal series it leads after a Game 1 win at home. Gronk's visibility helps push national attention toward a market that has been starved for postseason hockey.

What to watch: Watch whether Gronkowski makes an in-arena appearance as the Sabres-Canadiens series progresses. The series is in its early stages following Buffalo's Game 1 victory.