Mika Zibanejad scored his 29th goal for New York and Igor Shesterkin made 32 saves.
Having locked up home ice in the opening round of the playoffs with a victory over the Islanders on Thursday, the Rangers had their four-game winning streak snapped.
“I think intensity-wise, I thought we had it,” New York center Barclay Goodrow said. “Obviously, they’re preparing for the playoffs like we are also. It’s good to play one of those teams and it was a close-fought game. We did a lot of things well and some things we could have done better; little mistakes that cost us.”
New York finished the road portion of its regular season with 25 victories, tied for third most in team history.
Boston went 0 for 3 on the power play and hasn’t scored in its last 32 opportunities.
“I think our power play over the course of the year has been pretty good,” Pastrnak said. “The season’s long and sometimes you go through these slumps. It takes one goal and then you get rolling again.”
Ullmark is competing with Jeremy Swayman to be Boston’s No. 1 goalie in the playoffs.
“I don’t think about that at all,” he said. “I try to focus on what’s important right now. For me, it was this game. … If they ask me to play, I’ll play, and if it’s Sway that they want to play, I’ll be there for him and back him up.”
Charlie McAvoy made a nice cross-ice pass to Pastrnak, who fired the puck past Shesterkin from the left circle with 35 seconds left in the opening period.
Hall beat Shesterkin on a partial breakaway just over a minute into the second, slipping a wrist shot inside the far post. The 25-year-old Pastrnak assisted on the play for his 500th career point.
With Boston short-handed after Ullmark flipped the puck over the glass for a delay-of-game penalty early in the third, Zibanejad fired in a wrist shot from the bottom of the left circle.
But Frederic scored on a rebound with 10:23 to play.
Ullmark, who missed three games with an injury, robbed former Bruin Frank Vatrano midway through the second, using his glove to snare the one-timer. He even made a skate save off his own teammate, when the puck caromed off the skate of defenseman Hampus Lindholm.
Ullmark wasn’t worried about his time off.
“We’re so far into the season, everything is kind of in place,” he said. “I was just out a week, so I wasn’t concerned at all.”
Lindholm, a big trade deadline pickup, also was back after being sidelined with a lower-body injury for seven games.
New York forward Chris Kreider needs one goal to tie Adam Graves (52 in 1993-94) for second on the team’s single-season list. It’s also the last season the Rangers won the Stanley Cup.
Jaromir Jagr had the most in team history with 54 in 2005-06.
Center Andrew Copp, who recorded the first natural hat trick in an opening period by a Ranger in 72 years Thursday, didn’t play because of a lower-body injury. New York center Filip Chytil (upper body) also was sidelined. Coach Gerard Gallant said Friday neither injury is serious.
Rangers: Host Carolina on Tuesday in the opener of a three-game homestand that closes the regular season.
Bruins: At Montreal on Sunday. They have four games left in the regular season.
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