SAN DIEGO -- When Jo-Jo Reyes completed his forgettable relief appearance during Monday's 17-2 loss to the Padres, it was assumed that it would likely be a long time before he was given another chance to pitch for the Braves.

But until Wednesday, it wasn't known that in the process of allowing nine earned runs in 3 1/3 innings, Reyes injured his right knee.

The Braves plan to place Reyes on the 15-day disabled list on Thursday. They are expected to fill his spot on the roster with Mike Dunn, who has allowed three hits and completed 3 1/3 scoreless innings for Triple-A Gwinnett this season.

"[Reyes'] knee is bad," Braves manager Bobby Cox said. "It really is. It's not an excuse. It's really bad."

Reyes said that he felt his knee pop while backing up the plate after Chase Headley delivered an RBI single in the 10-run fourth inning. Headley was the second batter the Padres sent to the plate after chasing Braves starter Jair Jurrjens.

Knowing that it was his job to eat up innings in the lopsided affair, Reyes continued to pitch and didn't exit until surrendering a Tony Gwynn two-run double with two outs in the seventh inning.

"I tried to walk it off and I didn't think there was anything to it, because it wasn't slipping or giving out," Reyes said. "But it was still pretty painful the whole outing. Yesterday was probably the worst day. Today, it feels a little better."

By the time the Braves realized the significance of Reyes' knee ailment, left-hander Jonny Venters had already completed a side session for Triple-A Gwinnett on Thursday afternoon. Venters, who tossed 4 2/3 innings in a start on Monday, would have likely been called up if he would have been able to at least be available to pitch in relief during Thursday's series finale in San Diego.

Braves try Diaz in leadoff spot

SAN DIEGO -- The Braves exited Spring Training with some concerns about their lack of a true leadoff hitter, and through the first week of the regular season, Nate McLouth and Melky Cabrera have simply created more reason to be concerned.

Looking to jump-start an offense that has slumbered since scoring 16 runs on Opening Day, Braves manager Bobby Cox placed Matt Diaz in the leadoff role for Wednesday night's game against the Padres at PETCO Park. If he proves effective, Diaz could routinely be placed in this role, which he successfully handled for a couple of weeks late in the 2009 season.

"He's a .300-plus hitter," Cox said in reference to the .315 batting average Diaz has compiled since joining the Braves in 2006. "We'll give him a little bit of a go with it."

Through the first seven games of the season, Cox saw his leadoff hitters (Cabrera and McLouth) combine to hit .069 (2-for-29) with six walks and a .229 on-base percentage. McLouth came to Spring Training projected to fill the leadoff role, and then hit just .118 in 17 Grapefruit League games.

McLouth hit .254 with a .351 on-base percentage when he batted in the leadoff spot for the Braves last year. After the 28-year-old center fielder went on the disabled list in August, Cox saw Diaz enjoy a productive short stint at the top of his lineup.

During the 10 games that he batted leadoff for the Braves last year, Diaz hit .439 (18-for-41) with five walks and a .531 on-base percentage.

"I liked it last year," Diaz said. "It's a great spot to hit in our lineup. You hit in front of Chipper [Jones] and [Martin] Prado, so you get a lot of pitches to hit. You want to work counts, but you also don't want to lose your aggressiveness. That's the tricky part for me."

Entering the year, it appeared that Diaz might primarily platoon with Cabrera in left field. But with Cabrera hitting just .103 (3-for-29) and McLouth hitting .118 (2-for-17), Cox has already been forced to tinker with his original plans.

Cabrera, Hinske get their World Series rings

SAN DIEGO -- When Melky Cabrera and Eric Hinske arrived at PETCO Park to prepare for Wednesday night's game against the Padres, they were delighted to see that their former Yankees teammate Jerry Hairston Jr. had brought them the World Series rings that they earned in November.

Hairston, a Padres utility man, flew to New York on Tuesday in time to receive his World Series ring with his other former Yankees teammates. When he returned to PETCO Park on Wednesday, he delivered the rings and a congratulatory message to Hinske and Cabrera, who both joined the Braves during the offseason.

"He shook our hand and hugged both of us and said, 'This is from the team,'" Hinske said. "It was pretty cool."

Hinske joins Johnny Damon and Babe Ruth as the only players who have won a World Series with both the Yankees and Red Sox.

After helping Boston win a World Series championship in 2007, Hinske gained an American League championship ring for the contributions he made while helping the Rays reach the World Series. The Braves are just hoping that he is still with them in October, competing in the Fall Classic for the fourth straight year.

"It's a special thing," Hinske said. "A lot of guys play their whole careers and never even come close."

Jurrjens not concerned about shoulder

SAN DIEGO -- Jair Jurrjens still does not know exactly why his velocity was down during his forgettable outing against the Padres on Monday afternoon. But when asked again on Wednesday, the Braves right-hander said that he isn't worried about his right shoulder, which was inflamed during the early days of Spring Training.

"If there was something wrong, I would have felt it yesterday," Jurrjens said in reference to Tuesday's off-day.

Jurrjens, who allowed a career-high eight earned runs in 3 1/3 innings on Monday, went through his normal workouts on Wednesday afternoon. Shortly after arriving at PETCO Park, he was seen doing medicine ball drills with strength and conditioning coach Phil Falco.

During Monday's outing, Jurrjens' fastball primarily registered 87-89 mph. The 24-year-old right-hander's heater usually rests between 91-93 mph.

Braves to don baby blue throwback jerseys

SAN DIEGO -- When the Braves and Padres conclude their three-game series at PETCO Park on Thursday afternoon, they will be wearing the uniforms that their respective organizations displayed during the 1984 season.

This will provide Matt Diaz and many of Atlanta's older veterans the opportunity to wear the same baby-blue uniforms that Glenn Hubbard, Dale Murphy and the other Braves of yesteryear made so recognizable while playing on TBS on a nightly basis during the 1980s.

"I'm excited about it," said Diaz, who grew up a Braves fan. "Those guys were known as the loveable losers. We just want to be known as loveable."

During Thursday afternoon games played at PETCO Park, the Padres and the opposing team always wear throwback uniforms. During this week's event, each of the Braves and Padres will be wearing jersey No. 42 in observance of Jackie Robinson Day.