Only 48 hours after rolling up a season-high six goals in a 6-3 win on Long Island, the Bruins offense managed one goal, by Charlie Coyle in the first period.

Philip Tomasino scored a tiebreaking goal in the third period, Tristan Jarry made 31 saves and the Pittsburgh Penguins beat the Boston Bruins 2-1.

In the Black Friday battle between the two teams most associated with that color in their uniforms, Boston had its worst game since Joe Sacco took over as the interim coach and fell to the struggling Penguins, 2-1, on Friday at TD Garden. The Bruins host Montreal at 3 p.m. on Sunday for their 100th anniversary game.