SAN FRANCISCO -- The Giants' expectations of returning Casey McGehee to the starting lineup evaporated during a pregame workout Thursday, when the third baseman didn't respond physically as well as the club had hoped.
McGehee, 32, has missed five consecutive starts with a strained left knee.
"He came out and he ran. He's not quite ready," Giants manager Bruce Bochy said, adding that head athletic trainer Dave Groeschner estimated that McGehee needs at least one more day of rest.
Matt Duffy started his fifth game in a row Thursday at third base and sixth overall, including an April 11 assignment at second base. Duffy began the game batting .292 with four RBIs, matching Buster Posey's team lead.
• Bochy turned 60 today, though he couldn't find time to do much more to celebrate than go out to breakfast. Still, he was appreciative.
"It's a good number," Bochy said. "It beats the alternative. It reminds you a little bit that you're on the back side. But it's something to celebrate, I think."
• Jake Peavy, the Giants' scheduled starter vs. the D-backs on Friday, has won each of his last five starts against Arizona, though two of them occurred in 2009. Last year, the right-hander won back-to-back outings against the D-backs on Sept. 11 and 16, yielding two runs and 11 hits while striking out 12 in 13 1/3 innings.
Chris Haft is a reporter for MLB.com. Read his blog, Haft-Baked Ideas, and follow him on Twitter at @sfgiantsbeat. This story was not subject to the approval of Major League Baseball or its clubs.