Walker will serve as the opener for Monday's game against the Rays, Susan Slusser of the San Francisco Chronicle reports.

EDGE Analysis

Walker has been effective since the All-Star break, posting a 1.47 ERA and 0.76 WHIP in 18.1 innings over 12 appearances since mid-July. He's made eight starts this season but hasn't pitched more than three innings in any of his appearances, and he'll have another opportunity to serve as an opener Monday.