Red Sox first baseman Triston Casas is not in the starting lineup for Monday’s series opener against the Baltimore Orioles.

Connor Wong, usually Boston’s starting catcher, will start at first base in his place and Danny Jansen will set up behind the plate. Manager Alex Cora said the decision to sit Casas was matchup-based, saying he wanted both of the right-handed Wong and Jansen in the lineup to face Orioles left-hander Cade Povich, and that Casas hasn’t been hitting lefties well recently.

“He’s like in between right now,” Cora said. “He got a few hits early on but we’re trying to maximize the lineup. Connor is swinging the bat well, we’ve got Danny as a right-handed hitter here at Fenway, and Romy (Gonzalez) is swinging the bat well, so it’s more that than anything else.”

Though Casas has always been more productive against righties than lefties, this season he’s done less damage than in the past. Entering Monday he was batting .248 with a .795 OPS in 127 plate appearances against righties and .227 with a .715 OPS against lefties. By comparison, in 2023 those figures were .274/.865 against righties and .215/.817 against lefties.

Boston will feature seven righties in the lineup against Povich, who enters with a 2-7 record and 5.76 ERA. Lefties Jarren Duran and Rafael Devers will bat first and second and it will be all righties from there, starting with Rob Refsnyder batting third, Tyler O’Neill in the cleanup spot and Gonzalez batting fifth and starting at second base.

Trevor Story, who batted eighth in Sunday’s loss to the Chicago White Sox, was bumped up one spot and will bat seventh on Monday.

Brayan Bello (12-7, 4.75) is set to start for the Red Sox. After enduring a rocky start to the season the right-hander has been much steadier since the All-Star break, posting a 3.78 ERA over his last nine starts.

Jarren Duran LF

Rafael Devers 3B

Rob Refsnyder RF

Tyler O’Neill DH

Romy Gonzalez 2B

Connor Wong 1B

Trevor Story SS

Danny Jansen C

Ceddanne Rafaela CF

Brayan Bello P

When: 7:10 p.m.

Where: Fenway Park, Boston

Broadcast info: NESN, WEEI 93.7 FM, WCCM 1490 AM (Spanish)