Mets ace Jacob deGrom was scratched from Tuesday night’s start against the Cardinals because he was having trouble getting loose as he started to stretch ahead of his outing.

DeGrom underwent an MRI, which showed inflammation in his right lat. He will refrain from throwing for the next few days, the team said.

“He let us know earlier today that he had some tightness on his right side,” Mets manager Luis Rojas said about three hours before game time.

“I saw him before coming to the field and he was stretching, trying to feel his right side a little bit, and that’s when we started discussing whether he’s going to start or not.”

Rojas said the issue wasn’t evident before Tuesday.

DeGrom, a two-time NL Cy Young Award winner, had been baseball’s most dominant pitcher this season, with a major league-best 0.51 ERA in five starts, 59 strikeouts in 35 innings with just four walks. Still, he’s just 2-2.

The 32-year-old right-hander has reached 100 mph on 46 of 473 pitches this season and lowered his career ERA to 2.55, overtaking Hall of Famer Tom Seaver (2.57) as the Mets career leader.

Miguel Castro started in deGrom’s place.

Horse racing: The Belmont Stakes on June 5 in Elmont, N.Y., will limit attendance to 11,000 spectators for the third leg of the Triple Crown. All fans must submit proof of completed vaccination or a negative COVID-19 test to get into Belmont Park. If capacity limits increase before the race, more tickets will be made available. Last year’s Belmont Stakes was held without fans due to the pandemic. The Preakness Stakes on May 15 at Pimlico Race Course in Baltimore is limiting attendance to 10,000. The Kentucky Derby at Churchill Downs in Louisville, Ky., had 51,838 spectators Saturday.

NBA: The Lakers expect LeBron James to miss back-to-back games against the Clippers and Trail Blazers on Thursday and Friday to rest his injured right ankle, ESPN reported. It’s possible James could miss more games as he works through discomfort in the ankle that kept him out six weeks until a two-game return over last weekend. ... The Milwaukee Common Council approved a $750,000 settlement in a lawsuit brought by former Bucks player and current Rocket Sterling Brown over his 2018 arrest in which he was taken to the ground and shocked with a Taser. The incident started when Brown was approached by police over a parking violation. The Milwaukee Journal Sentinel reported that the agreement also requires the city to commit to changes in the police department’s standard operating procedures.

NFL: The Ravens signed two-time Pro Bowl T Alejandro Villanueva to a two-year deal worth $14 million and $8 million guaranteed, ESPN reported. Villanueva, 32, started at left tackle for the Steelers for the last six seasons but likely will play on the right side for the rival Ravens.

WNBA: The Dream promoted Mike Petersen, 63, to interim coach a day after Baylor hired Nicki Collen to replace Hall of Famer Kim Mulkey, who left for LSU.