Sandoval (biceps) went three innings, allowing one earned run on one hit and one walk while striking out four Wednesday for Double-A Portland, reports Christopher Smith of MassLive.com.
Sandoval -- who has yet to make his debut for Boston after signing a two-year, $18.25 million contract prior to last season -- built up to three innings during his third rehab outing Wednesday, and he'll likely require a couple more appearances before coming off the shelf. The 29-year-old, whose rehab appearances this season have been his first game action since 2024, was initially working his way back from internal brace surgery on his elbow before left biceps discomfort surfaced during the spring to delay his return.