The 26-year-old German started 10 of the final 16 games of the regular season, going 7-3-0 with a 2.32 goals-against average and .925 save percentage. Grubauer's 2.06 GAA and .933 save percentage are the best among NHL goalies since Oct. 27.
"I just think that Grubi deserves the opportunity," coach Barry Trotz said Tuesday, a day after telling Grubauer of his decision. "It sort of evolved all year. There wasn't a date or anything like that. It just evolved and Grubi got more games and a bigger body of work."
Grubauer called it a privilege to start after spending the past three full seasons as the backup to Holtby, who won the 2016 Vezina Trophy as the NHL's best goaltender. It could be a short-lived privilege if he struggles because Trotz said his decision is only for Game 1 on Thursday night and the Capitals are going "game by game."
The opener will be Grubauer's second career start in the Stanley Cup playoffs. Grubauer started a game against the New York Islanders in the first round in 2015 when Holtby was sick and entered in relief once in 2017.
"It doesn't change how we go about our business," Blue Jackets coach John Tortorella said. "We're just concerned about our game."
Grubauer led Windsor to the Ontario Hockey League title and won the Memorial Cup in 2010. He also helped Germany qualify for the 2018 Olympics. But it's this recent stretch that gives him the most confidence going into the playoffs.
"It helps playing more and more," Grubauer said. "The more you get on the ice, the more experience you get. You see different situations and different teams. If you sit on the bench, you can get good from watching, but you've got to get the experience."
He will likely see a lot of Columbus captain Nick Foligno, who is back after missing the final six games of the regular season with a lower-body injury. Foligno gives the Blue Jackets some net-crashing presence and will be in and around the crease often.
"I honestly feel great," Foligno said after centering Oliver Bjorkstrand and Josh Anderson in practice on what is now the deep Blue Jackets' third line. "I've played this game long enough to know how you have to prepare during an injury to make sure you're feeling good mentally and physically when you get back."
Holtby has never sat on the bench for a Stanley Cup playoff game. Michal Neuvirth started all nine games for Washington in 2011 before injuries to him and Tomas Vokoun pressed Holtby into duty in 2012.
The 28-year-old has started 59 of the past 60 Capitals playoff games. But his struggles down the stretch -- a 3.75 GAA and .886 save percentage in his final 17 appearances -- cost him the ability to go into another postseason as the guy even after showing improvements following his four-game "reset."
Trotz said Holtby was a pro and told him: "If you put me in the net, my job is to stop the puck. If I get that opportunity, I'll stop the puck." He was similarly gracious after practice about the demotion.
"My job is just to focus on my game, getting it the best it can get to," said Holtby, who closed the season 5-1-0 with a 2.67 GAA and .911 save percentage . "Coach's decision who plays or not doesn't have anything to do with me. I'll just focus one practice at a time, trying to be a positive influence around the team and go from there."
Holtby said in March it was good to "clear the team's head with that kind of stigma that's kind of going on with me in net." With Holtby and Grubauer splitting time down the stretch, the Capitals won 12 of their 15 final games.
"I think we have two good goalies who can play," defenseman Dmitry Orlov said. "Grubi was good for us all season. It's not easy to be second goalie and not play some games. You need to always be prepared in practice. I think he did a good job like a professional player, and I think he's got confidence right now."
Capitals C Jay Beagle, who missed the final three games of the regular season with an upper-body injury, did not practice Tuesday but skated afterward. Trotz is calling Beagle day-to-day. ... Capitals RW T.J. Oshie said he feels great after resting a nagging lower-body injury and expects to be in the lineup for Game 1.
AP Sports Writer Mitch Stacy in Columbus, Ohio, contributed.
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