SAN DIEGO -- As he prepared for the final game at Petco Park in 2012, Padres manager Bud Black reflected on what has keyed his club's turnaround in home games over the second half of the season.

After struggling through the first half both at home and on the road, the Padres have gone 25-11 at Petco Park since July 16, and won nine of 11 home series, pending the outcome of the rubber match against San Francisco on Sunday.

While Black mentioned the comforts of home being a contributor to the second-half success, he also pointed to continuity on the roster as perhaps the most important thing of all.

"I think that was a factor in how we were playing and our momentum," Black said. "I don't mean to overstate it, but the continuity of the group as far as being together was stable. Once we got the middle infield situation resolved, once [Carlos Quentin] got back on the active roster, the position players pretty much stayed the same."

Black also stressed that despite the ballpark's reputation for favoring pitchers, the approach to the way the Padres play at home has to be the same.

"I do think our guys understand that there's no difference between how you go about a baseball game, whether it's on the road or at home," Black said. "If you play your game, whatever that game is, whether it's Carlos Quentin's game or Chase Headley's game, Everth Cabrera's game -- you play the same way. You don't take ballpark factors into consideration, you just play baseball."

The Padres have played historically well at home in the second half, as the .694 winning percentage is the highest mark ever for the franchise, topping the 1998 and 1996 clubs, who both finished 20-11 (.645) over the second half of the season.

"Teams should play well at home," Black said, "because that's the ballpark that you're accustomed to. That's why in any professional sport, home records are better than road records. So, it was good to see our guys understand that and get that."

Volquez exits in fifth against Giants

SAN DIEGO -- Edinson Volquez exited Sunday's game against the San Francisco Giants in the fifth inning due to cramps in his legs.

Volquez threw one pitch in the fifth before stepping off the mound and signaling for a visit from manager Bud Black and the team trainer. Black then called for Brad Boxberger to replace Volquez, who walked off the field with the trainer at his side.

"It's a huge physical distraction," Black said. "I don't think it had anything to do with anything other than he didn't feel comfortable. His legs were not underneath him. That's going to affect his delivery for sure. He'd probably be the first to tell you that some of the walks he allowed, or some of the base hits he allowed weren't because of the cramping."

Prior to the premature exit, Volquez allowed two runs on six hits in his final start of 2012. He struck out four, walked three and threw 71 pitches, finishing his first campaign with San Diego with a 11-11 record and 4.14 ERA.

Short hops

• With Yasmani Grandal making his 50th start of the season at catcher on Sunday, three different Padres players have made 50 or more starts behind the plate this season (Nick Hundley started 56 games and John Baker started in 51).

According the the Elias Sports Bureau, no Major League team since 1900 has had three players make 50 or more starts at catcher in the same season.