SAN DIEGO -- After some deliberation, the Giants cleared roster room Saturday night for starting pitcher Patrick Misch by placing infielder Rich Aurilia on the 15-day disabled list with a strained right hamstring, retroactive to Thursday.

More personnel moves are likely to follow in the next week or two. The Giants are five games into a stretch of 31 games in 30 days, including a doubleheader Aug. 13 at Pittsburgh that might force the club to add a 13th pitcher. Before that, right-hander Russ Ortiz is likely to be activated from the disabled list, assuming he emerges healthy from his injury rehabilitation start Saturday with Triple-A Fresno.

And the possibility that a need could arise at a particular position remains ever-present.

"Our roster's going to be day-to-day for a while," general manager Brian Sabean said.

The Giants didn't announce the move until shortly before gametime, generating speculation that Sabean was trying to engineer a trade involving a veteran such as Ray Durham or Ryan Klesko.

"There were a couple of scenarios," Sabean admitted. But he noted that he ran out of time to complete a deal -- "We had to get it in before the game" -- besides the simple fact that the Giants re-evaluated Aurilia's condition during pregame drills. Aurilia, who hurt himself running the bases Wednesday in Los Angeles, indicated before batting practice that he felt better, but that wasn't enough for the Giants' brass.

Shelving Aurilia also enabled the Giants to keep outfielders Fred Lewis and Rajai Davis on the roster for further evaluation of their skills. Either one, particularly Davis, might have been vulnerable to being optioned to Fresno.

But, as Sabean said, "Right now, this was the cleanest move for us. ... No sense in sending out an able body."

Back to basics: Except for his win-loss record, Matt Cain has resumed looking like himself again -- piling up strikeouts and remaining hard to hit.

The difference, Cain said, has been his mental approach. Simple as it sounds, he has regained belief in his fastball and his ability to get ahead on the count with it.

"I feel like my mechanics are right," Cain said. "The biggest thing for me is having the confidence in throwing strikes. Everything else will kind of fall into place."

Cain said that he adjusted his attitude mostly by analyzing other pitchers during his four days between starts. Ex-teammate Matt Morris, he said, served as a solid example.

"He was always going to throw strikes and not walk many guys, and he gave himself a chance that way," said Cain, who also mentioned that watching Los Angeles' Brad Penny last Tuesday helped.

Merely receiving advice, Cain said, would have had less impact than watching fellow pitchers.

"Some of that stuff is easy to be said, but when you actually see somebody do it, it definitely is reassuring," Cain said.

After allowing one run in back-to-back starts June 10 and 16 -- a span in which he yielded only eight hits in 15 innings -- Cain fell into a rut. He posted a 6.54 ERA in his next six starts, walking 19 and striking out 20 in 31 2/3 innings. But in his last two starts, Cain has struck out 18 and walked three in 14 1/3 innings while allowing five runs.

Injury update: Right-hander Kevin Correia said that he was no longer bothered by his left ankle, which kept him out of Friday night's game.

"Right now I feel 100 percent," Correia said, revealing that he tweaked his ankle while running before Thursday's game at Los Angeles, although he pitched 1 1/3 shutout innings that night.

Coming up: The Giants conclude their three-game series in San Diego and their six-game trip Sunday with a finale starting at 1:05 p.m. PT. San Diego resident Noah Lowry, who's 6-1 in his last seven starts, will oppose Padres right-hander Justin Germano.