ST. PETERSBURG -- Left-handed pitcher Aaron Poreda, a key component in the trade that sent Jake Peavy to the White Sox last July, has been pitching well since he earned a promotion from Double-A San Antonio to Triple-A Portland.

In his last outing on Saturday, Poreda struck out three and didn't walk a batter over three scoreless innings.

Overall, Poreda hasn't allowed a run in Portland in four appearances. In 7 1/3 innings, he has allowed three hits with seven strikeouts and seven walks.

The walks -- and command, in general -- are a big reason Poreda began the season with San Antonio. He had a 2.52 ERA there with 25 strikeouts and 26 walks in 25 innings.

Still, there's no denying that Poreda has electric stuff, as Randy Smith, who is the Padres director of player development, said recently.

"Guys look uncomfortable hitting against him," Smith said of Poreda.

Between San Antonio and Portland, opponents are hitting .191 against Poreda in 2010.

Headley takes pride in work at third base

ST. PETERSBURG -- When Padres third baseman Chase Headley committed an error in the ninth inning of Wednesday's 5-4 victory over the Rays, it marked his first miscue at third base in 100 chances.

Headley, who has seven errors this season, made his last error May 9 before he bounced a throw to first base that Adrian Gonzalez couldn't corral. That led to an unearned run later in the inning.

Still, Headley has found comfort in knowing that he's settling well back into his natural position after two seasons away playing in left field.

"It's something that I've worked hard on," Headley said. "When I came into this year, I wanted to be a good third baseman. I take pride in it."

Headley made five errors in the first 10 games of the season, though some of that can be attributed to a Spring Training where he, for whatever reason, didn't get much action at the hot corner.

"Nothing simulates a ground ball in a game, and in Spring Training, he didn't get a lot of reps," Padres manager Bud Black said. "As each week has passed, I've seen much more comfort at third base with all plays. He's made some fabulous plays."

Padres set for winning Interleague record

ST. PETERSBURG -- Padres manager Bud Black was asked Thursday about the success of his team in Interleague Play -- a question he hasn't had to field since taking over as the manager before the 2007 season.

The Padres entered Thursday's game against the Rays -- the last Interleague game they'll play this season -- with a 9-5 record.

San Diego's victory on Tuesday clinched a winning record in Interleague Play for just the second time in franchise history. Since Interleague Play began 14 years ago, the Padres have finished above .500 in 1999 (11-4) and at .500 in 1997 (8-8).

"The only difference is we're playing better," Black said. "I don't think that you can draw any conclusions from it. We've played better fundamental baseball."

That the Padres went 4-2 against the Mariners and 2-1 against the Orioles -- two teams that are well under .500 this season -- probably didn't hurt, either.

Stairs can jog but not run yet on knee

ST. PETERSBURG -- The good news regarding Padres veteran Matt Stairs is that he's now doing some light jogging on his sore right knee and is able to take batting practice.

The bad news is that the 42-year-old outfielder still has a ways to go before the Padres are prepared to reinstate him from the 15-day disabled list.

Stairs has been on the disabled list since June 11 (retroactive to June 7) with a strained right knee that the team later found some other issues with -- none, they believe, that will require surgery.

"He progressing. He's hitting on-field, but the one thing he hasn't been able to do is run with intensity," Padres manager Bud Black said. "He's not quite to that stage yet. He's doing some light jogging but the knee is still a little sore."