Updated

The Oakland Athletics have summoned Sonny Gray from the minors to make his first major league start Saturday in Toronto against the Blue Jays.

Gray, who had his contract selected from Triple-A Sacramento, was Oakland's first-round pick in the 2011 draft. The 23-year-old right-hander earned his first promotion to the majors last month, tossing four scoreless in two relief appearances.

A star at Vanderbilt, Gray has posted a 10-7 record with a 3.42 ERA in 20 starts for the River Cats this season.

Infielder Adam Rosales, for the third time in the past 11 days, was designated for assignment to clear a roster spot.