WASHINGTON – Playoff rookie Braden Holtby followed up a shaky outing with a superb one by making 44 saves Thursday night, and Alexander Semin scored the go-ahead goal, leading the Washington Capitals to a 2-1 victory over the reigning Stanley Cup champion Boston Bruins that tied the first-round series at two games apiece.

Marcus Johansson put the puck past Tim Thomas less than 1 1/2 minutes after the opening faceoff, but Boston’s Rich Peverley tied it later in the first period. Semin put Washington ahead for good with 1:17 left in the second on a power-play goal, his second score of the series.

The best-of-seven Eastern Conference series shifts back to Boston for Game 5 on Saturday. Game 6 will be in Washington on Sunday.

Washington was 25-0-1 during the regular season when leading after two periods, and Holtby continued that trend, inspiring repeated chants of “Holt-bee! Holt-bee!” from the red-wearing spectators. After things got rowdy in Game 3, the Capitals did it with discipline Thursday: The hosts were called for only one penalty.

It’s been a tight series all the way, with neither team leading by more than one goal at any moment.

Semin decided things Thursday by zipping a wrister from the left circle past Thomas, after Alex Ovechkin and Keith Aucoin set it up with assists.

That came on Washington’s third power play of the game. The Bruins had zero extra-skater chances through the first two periods, as the Capitals played precisely the type of quiet hockey that their coach, Dale Hunter, said he really wanted to see.

Washington wasn’t called for a penalty until there were just less than 10 minutes left in the third period.

DEVILS 4, PANTHERS 0: In Newark, N.J., Martin Brodeur bounced back from his shortest postseason performance with a record-setting 24th Stanley Cup playoff shutout, leading the Devils past Florida, tying the teams’ first-round series at 2.

Brodeur made 26 saves in taking over sole possession of the postseason shutout mark from Patrick Roy. The 39-year-old goaltender also added his second assist of the series, giving him 10 for his career, four behind all-time leader Grant Fuhr.

The effort came two days after Brodeur was lifted after giving up three goals in 22:18 in a 4-3 loss.

Zach Parise, Steve Bernier, Travis Zajac and Ilya Kovalchuk scored for New Jersey.

Game 5 of the best-of-7 series will be Saturday in Florida.

Florida had an excuse of sorts. Defenseman Jason Garrison, one of the quarterbacks of the Panthers’ power play, was sidelined with a lower back injury.