PORT ST. LUCIE, Fla. (AP) — Right-hander Frankie Montas, who signed a two-year, $34 million free-agent contract in December with the New York Mets, will be shut down from pitching for six to eight weeks because of a strained back.

Mets manager Carlos Mendoza said Monday it was a high-grade lat strain and that Montas was heading to New York for an injection. After the shutdown, Montas will need a spring training-like buildup, meaning Montas won’t pitch until May at earliest.

The injury creates uncertainty for a starting rotation that went through a makeover during the offseason. Mendoza said Montas’ injury wouldn’t necessarily mean the Mets are no longer going with a six-man rotation.

“We’ve got options,” Mendoza said. “It’s still too early. We will continue to have those conversations.”

The Mets filled holes in their rotation with free-agent deals for Montas, Sean Manaea and Griffin Canning and bolstered their bullpen by picking up A.J. Minter and former All-Star closer Clay Holmes.

Montas missed most of the 2023 season because of shoulder surgery. He returned last season but went 7-11 with a 4.84 ERA while playing for the Cincinnati Reds and Milwaukee Brewers.