UMass Lowell and Providence College squared off in a defensive battle for the ages Friday night at TD Garden in the 2016 Hockey East tournament semifinals.

Each team scored one goal in regulation, then went without one for more than two-and-a-half 20-minute overtime periods. It wasn’t until the 12:27 mark of triple overtime that UMass Lowell center A.J. White finally put a puck past Providence goaltender Nick Ellis, and the manner in which he did so caused a great deal of controversy.

A centering pass from Michael Fallon deflected off White’s right skate and into the net, prompting the referee to initially wave the goal off. Upon further review, however, officials determined that although White knocked the puck in with his skate, he did not exhibit a distinct kicking motion.

The goal counted, and the River Hawks emerged with a 2-1 win in the ninth-longest game in NCAA hockey history.

The result spoiled a brilliant effort by Ellis, who finished with 42 saves. Lowell goalie Kevin Boyle — the Hockey East Co-Player of the Year this season — was even better, stopping 58 of the 59 shots he faced.

The win secured the River Hawks’ fourth consecutive appearance in the Hockey East championship game, which is set for Saturday at 7 p.m. ET. They’ll play the winner of semifinal No. 2 between Boston College and Northeastern, which, thanks to the marathon game that preceded it, was pushed back to 10:34 p.m. Friday.