The Red Sox released La Sorsa on Thursday.
Contreras (illness) is absent from the lineup for Thursday's game against the White Sox.
Stone (shoulder) will begin a rehab assignment at Triple-A Oklahoma City on Thursday.
Muncy went 1-for-4 with a three-run home run in a loss to the Cubs on Wednesday.
Betts went 4-for-5 with a run in a loss to the Cubs on Wednesday.
Casas (abdomen/knee) underwent arthroscopic surgery on his left wrist Thursday.
Abreu went 2-for-3 with a walk, a stolen base, a solo home run and two additional runs scored in Wednesday's 4-0 win over the White Sox.
Miller (shoulder/back) allowed a solo home run and struck out three over two innings in his first rehab appearance with Triple-A Oklahoma City on Wednesday.
Story (sports hernia) will be re-evaluated at the end of the team's current homestand to determine when he can begin a rehab assignment, MLB.com reports.
Monasterio went 1-for-2 with a stolen base and an RBI in Wednesday's 4-0 win over the White Sox.
