PHILADELPHIA -- Had Padres center fielder Cameron Maybin not suffered a strained left hip flexor Sunday, Chris Denorfia probably wouldn't have found himself in center field in the seventh inning.

It's a good thing he was there, though, because Denorfia pulled back a certain two-run home run by Raul Ibanez, leaping at the wall in center field with his glove extended over the fence.

Prior to the Padres' 5-4 win over the Phillies on Monday, members of the Padres were still buzzing.

"That was a hell of a catch," Padres manager Bud Black said on Monday.

The Padres lost the game, 5-3, though Denorfia's catch wasn't lost on his teammates, his manager, the sold-out crowd at Citizens Bank Park -- which gave him a standing ovation -- or even Denorfia's parents, who drove from their home in Connecticut to watch the game.

"The angle was as such where I ended up running straight back, and I had a chance to look at the fence a couple of times," said Denorfia, who stole home on Monday. "It's a timing play."

On Thursday in Miami, Maybin made a similar catch in the first inning of a victory over the Marlins, robbing former teammate Logan Morrison of a home run with a catch at the wall in center field at Sun Life Stadium.

"We've had some good catches," Black said.

Padres focused on shoring up defense

PHILADELPHIA -- Looking for a reason why the Padres had won 16 fewer games this season than they did at the 103-game mark a year ago?

Don't be so quick to assign all of the blame to the post-Adrian Gonzalez offense that has been shut out 15 times this season.

The Padres' defense -- one of the integral components of a team that won 90 games a year ago -- has struggled this season in converting balls in play into outs.

"The defense is not where we need it to be for the type of games we play, the tight, low-scoring games," said Padres manager Bud Black. "Especially playing at PETCO Park ... runs are at a premium."

Over their first 103 games last season, the Padres made 44 errors which helped account for 19 unearned runs. San Diego was 61-42 at that point in the season.

This season, the Padres were 45-58 after a 5-4 win over the Phillies on Monday. They had allowed 50 unearned runs and committed 68 errors.

"Heading into Spring Training, I felt our defense would be improved at every position expect first base ... that has not been the case," Padres general manager Jed Hoyer said.

"We have been much more mistake-prone this season, and it has cost us in many close games. It is a clear area of [needed] improvement as an organization."

Third baseman Chase Headley is the only returning infield starter from last season, as second baseman Orlando Hudson, shortstop Jason Bartlett and a host of first basemen are new. Bartlett finished Monday with 17 errors this season while Headley had 11.

The Padres' pitchers had a combined nine errors this season.

Black said defense is such a priority because San Diego plays so many close games and because its starting pitching staff relies more on ground balls than strikeouts. Going into Monday's game against the Phillies, the Padres starting pitchers had the eighth-best ground-ball percentage (58.3) in the Major Leagues.

"We're not going to lead the league in strikeouts ... we're not a strikeout-heavy staff," Black said. "I do think there's some strikeouts in our bullpen, but we know that there's going to be a lot of balls in play.

"We need to convert those into outs."

Maybin nursing strained left hip flexor

PHILADELPHIA -- The Padres were shorthanded on Monday in their 5-4 win over the Phillies, as outfielder Cameron Maybin did not play because of a strained left hip flexor that he suffered Sunday.

Maybin said he suffered the injury running down the first-base line on a ground ball in the third inning. Maybin stayed in the game until the fourth inning, when manager Bud Black decided to pull him as a precaution.

Black said Monday that Maybin was still sore and that "we're hoping it resolves itself in the next couple of days."

The injury came into play during Monday's game when outfielders Ryan Ludwick and Chris Denorfia collided in the fourth inning. Ludwick, who was playing right field, later left the game, saying he felt woozy. Denorfia shifted from center field to right, while Will Venable entered in center.

Black said before the game that the team likely won't add an outfielder for the series against the D-backs that begins Tuesday at PETCO Park.

Maybin's average had risen to .283 when he exited the game Sunday, the highest that it had been since the second game of the season.

Overall, Maybin began Monday hitting .320 on the road this season, with five home runs and 22 RBIs in 172 at-bats, compared to .237 with one home run and five RBIs in 139 home at-bats. He had 14 hits and batted .538 while scoring eight runs last week, which propelled him to a share of the National League Player of the Week honors.

Worth noting

• Padres catcher Nick Hundley played catch for the second time in as many days on Monday as he works his way back from surgery on his right elbow on July 8. He hopes to be able to hit during live batting practice later in the week.

• Pitcher Clayton Richard, on the disabled list since July 5 with a strained left shoulder, played catch Sunday. There's no timetable for his return.