Cabrera had an MRI earlier on Thursday that determined the soreness he's experienced in recent days was indeed a strain.
The Padres will purchase the contract of infielder Lance Zawadzki from Triple-A Portland. He will be added to the 40-man roster and the 25-man active roster in time for Friday's game against the Brewers.
Zawadzki hit .308 in Spring Training and impressed manager Bud Black and the coaching staff with his play at shortstop, especially during the second half of camp.
Zawadzki is hitting .162 in 68 at-bats with Triple-A Portland.
To make room for Zawadzki on the 40-man roster, the Padres moved infielder Matt Antonelli to the 60-day disabled list. Antonelli had surgery on Thursday to repair a broken left hamate bone.
Jerry Hairston Jr. got the start at shortstop and hit leadoff Thursday as the Padres opened a four-game series against the Brewers at PETCO Park. He'll likely continue to play there on an everyday basis.
Cabrera hasn't started a game since Saturday against the Reds when he was hit on the left knee by a slider from Reds' pitcher Johnny Cueto. The soreness in the knee subsided but then came the pain in the hamstring.