Philadelphia Phillies first baseman Bryce Harper (3) hits a solo home run during the first inning against the Arizona Diamondbacks in Game 1 of the NLCS for the 2023 MLB playoffs at Citizens Bank Park. Bill Streicher-USA TODAY Sports

Watch: Bryce Harper blows out his birthday candles with HR

Bryce Harper turned 31 on Monday. That birthday got a lot happier in the first inning.

Harper hit a solo shot off Arizona Diamondbacks starter Zac Gallen in to give the Philadelphia Phillies a 2-0 lead in Game 1 of the National League Championship Series. The Phillies held off Arizona, 5-3.

As he neared home plate, Harper held up three fingers on one hand and one on the other — then blew out the "candles."

Broadcaster Brian Anderson first thought Harper was counting his postseason home runs, and it was his fourth homer of the 2023 playoffs. But the way Harper held up his fingers made it clear he was celebrating his birthday. 

It's also the 15th postseason home run of his career, and the first time Harper has played on his birthday.

That's one behind designated hitter Kyle Schwarber, who led off the first inning with his 16th postseason homer.

It was also Schwarber's fourth leadoff home run in the playoffs, which set an MLB record.

Harper's shot was also Philadelphia's 15th home run in seven games. But one inning later, Nick Castellanos hit their 16th and his fifth home run in the last three games.

Five home runs in eight playoff plate appearances is an amazing hot streak for Castellanos. The greatest birthday present the Phillies could give Harper is a 1-0 series lead. 

They're well on their way to making it a 31st birthday to remember.

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