Benoit Pouliot scored twice in regulation for the Rangers, who bounced back from a home loss to Edmonton the night before and won for the fifth time in six games.
The Penguins had won all four of their previous shootouts this season and 14 of their past 15 overall.
Zuccarello, the second New York shooter in the tiebreaker, tucked a backhand under the pads of Marc-Andre Fleury — who had not allowed a shootout goal all season. Evgeni Malkin beat Henrik Lundqvist to extend the game before Richards flipped a shot past Fleury to end it.
For six months, it's a really good accomplishment. But as soon as April [11, the end of the regular season] comes around, no one thinks about the regular season anymore. For six months, it's a real battle to get into the playoffs in the NHL these days. There are a lot of good teams, and it takes consistency over a long time.
— Ducks coach Bruce Boudreau on clinching a playoff berth after a win against the Islanders on Saturday