Updated

San Francisco, CA (SportsNetwork.com) - Jake Peavy's lingering back issues forced the struggling San Francisco Giants to place the veteran pitcher on the 15-day disabled list Saturday.

The move comes less than 24 hours after Peavy lasted just 3 2/3 innings in the Giants' eighth straight loss, a 9-0 setback to Arizona in which the right- hander was tagged for four runs on eight hits.

Peavy had his season debut pushed back to last Sunday due to discomfort in his back. He pitched just four innings in that outing and also received the loss after surrendering four runs against San Diego.

The Giants re-signed the 33-year-old former NL Cy Young Award winner to a two- year, $24 million contract in December. Peavy earned the deal by going 6-2 with a 2.17 ERA over 12 regular-season starts after being acquired by San Francisco from Boston in late July.

Catcher Andrew Susac was promoted from Triple-A Sacramento to take the available roster spot.

One of the team's top prospects, Susac hit .273 with three home runs and 19 RBI in a 35-game audition for the Giants late last season.