Kyle Schwarber is staying in Philadelphia — and it could have a ripple effect on whether the Mets retain Pete Alonso.

The Phillies re-signed the NL home run champion to a five-year, $150 million contract on Tuesday, The Post’s Joel Sherman confirmed.

ESPN first reported the transaction, and it’s the largest contract ever signed by a designated hitter.

Schwarber re-upping in Philadelphia is the first major free-agency move among position players and will have league-wide effects, particularly with the rival Mets.

Schwarber drew interest from the Mets while they considered life without Alonso, The Post reported, while the Reds, Orioles, Red Sox and even the Pirates expressed a willingness to sign him, per ESPN.

The Phillies made a late push, though, and they retained the 32-year-old lefty slugger.

Kyle Schwarber of the Philadelphia Phillies reacts after hitting a solo home run against the Los Angeles Dodgers.Kyle Schwarber is staying in Philly. Getty Images

Schwarber hit a career-high 56 homers with an MLB-best 132 RBIs, landing on the All-Star team by slashing .240/.365/563 with a career-best .928 OPS.

This season marked his fourth with the Phillies, and it’s possible this is the last large contract he signs.

Pete Alonso of the New York Mets reacts after he couldn't field a ball clean to allow a run to tie the game.Pete Alonso is now the top power bat on the market. Charles Wenzelberg/New York Post

Schwarber has slugged 340 career homers and tallied at least 94 RBIs in each season with the Phillies, including 100-plus in each of the last three years.

With Schwarber now signed, it leaves Alonso as the premier power bat on the market. Kyle Tucker is likely the top free agent and should command much more than Alonso.

The Mets and Alonso came to an agreement on a two-year deal worth $54 million with an opt-out clause last offseason, and Alonso opted out after a strong 2025 season.

Alonso did not land the long-term deal he sought last offseason and is attempting to do so this offseason, though the Mets’ willingness to hand out such a deal remains to be seen.

The Post reported that the Red Sox and Orioles are among the suitors that will meet with Alonso at his Tampa home.

Alex Bregman is another top free agent and there could be potential trade candidates, although there’s certainly a sentimental connection with Alonso and the Mets.

Cody Belliner fits the Mets in a lot of ways due to his versatility, although the Yankees and others provide stiff competition.