The Red Sox have officially added newly acquired first baseman Garrett Cooper to the big league roster, and to clear space the club designated infielder Pablo Reyes for assignment.

Reyes came into the season as the presumed utility man off the bench, but due to a series of injuries Reyes has gotten more playing time than originally expected. The 30-year-old batted .183 with a .451 OPS in 21 games while playing at all four infield positions, plus pitcher.

Cooper, meanwhile, is expected to take over as the everyday first baseman until Triston Casas returns from injury. The 33-year-old batted .270 with a home run and six RBI in 12 games with the Cubs this season, and he is two years removed from an All-Star campaign in 2022.

With second baseman Vaughn Grissom expected to be activated before Tuesday’s series opener against the San Francisco Giants, the Red Sox are effectively shaking up both their infield and bench. Going forward the club will likely go with an infield consisting of Cooper at first, Grissom at second, Ceddanne Rafaela at short and Rafael Devers at third, with Bobby Dalbec shifting back to the primary backup at the corner infield spots and one of David Hamilton or Enmanuel Valdez as the back-up middle infielder.

Romy Gonzalez, who is currently out with a sprained left wrist, could also fill Reyes old utility role when he returns as well.