Harvard returned the Warriors' serve, and the Warriors set up for the match-clinching kill.
Cardet, following the play all the way, reponded with a resounding block on outside hitter Jason Hartzel that tied the game at 31-31 and energized the crowd.
The Warriors hit the next two balls into the net to give the Crimson the 33-31 third game win.
Denham dictated the Harvard offense in the fourth game, recording seven kills in the game to give the Crimson a 24-19 lead and eventually the convincing 30-21 win.
East Stroudsburg, blitzed by the surprising Harvard run, faltered in the crucial fifth game.
Stevenson started the game strongly for the Crimson, recording four kills to give Harvard the 4-1 lead. Kowell continued the attack with two kills and a block that increased the advantage to 8-2.
Denham added two more kills and a couple of tips to end the fifth game 15-7 and complete the remarkable come-from-behind victory.
The Crimson's next game is Wednesday at Roger Williams. Harvard returns to conference play against Vassar on Saturday.