Alvarez went 3-for-4 with a double, an RBI single and a run during Tuesday's 7-5 loss to the Angels.
Alvarez was excellent in his first career start, clubbing a double in his first at-bat before being driven in by JJ Bleday and then plating Shea Langeliers on an infield single in the eighth. The 29-year-old Alvarez had his contract selected Saturday, marking his first big-league stint since entering the minors in 2016. With Abraham Toro (hamstring) on the injured list, Alvarez should have some opportunities at third base, though he'll have to compete with Tyler Nevin for playing time at the hot corner.