The Giants are looking into whether Lowry had the same injury as former 49ers quarterback Tim Rattay, who was diagnosed with exertional compartment syndrome in his throwing arm in 2004.
The condition is uncommon in the arm -- it's almost always a lower-leg injury -- so if the Rattay case is a match, it could serve as a helpful example as Lowry begins his comeback. A team official said the Giants medical staff would be in touch with the 49ers staff to compare notes.
Rattay, like Lowry, had trouble gripping the ball because his forearm muscles were too tight. He had surgery to snip the thin sheath around the muscle and relieve the pressure, an operation just like the one Lowry had last week.
Unlike Lowry, the 49ers quarterback was in no hurry to return because his operation came at the end of the season.
The Giants are uncertain how long Lowry will be out -- in part because they can't find a pitcher who has undergone the same procedure -- but their current estimate is that he will be sidelined through mid-April.
Campaign for fifth spot
Patrick Misch, a candidate for the fifth-starter's job, allowed two runs in 3-1/3 innings during a 10-2 loss to the Colorado Rockies at Scottsdale Stadium.
Misch's ERA stands at 3.68 after four appearances (one start). He is competing with Jonathan Sanchez, who pitched well Saturday, for the fifth starter's job.
"Very encouraging," manager Bruce Bochy said of Sanchez and Misch. "I thought Misch threw the ball well today. We need to establish some depth in the rotation, so it's nice to have some choices."
Infielder Emmanuel Burriss played with his name misspelled as "Burris" because the corrected version of his jersey is still on order. ... Barry Zito (0-2, 22.09 ERA) starts today against the Kansas City Royals in Surprise. ... Outfielder Clay Timper hit a solo home run in the ninth, his first hit in 10 at-bats this spring.
-- Daniel Brown, MediaNews staff