Leaping catches and other big plays likely will dominant the nightly TV sports news. But for Bears general manager Phil Emery, the highlight of training camp will be the intense position battles.

"The overall theme for me is competition," Emery said Wednesday as the Bears kicked off training camp at Olivet Nazarene University in Bourbonnais for the 13th straight summer.

"There are a lot of unsettled positions on this team for the 53-man roster and there are implications for the 46-man game-day roster and our practice squad. [There is a] tremendous group of players in the mix in terms of the quality and number that we have."

Phil Emery addresses the media from Bears training camp at Olivet Nazarene University.

Emery said the Bears would keep 9 or 10 defensive linemen on a unit that was bolstered during the offseason with the signings of free agent ends Jared Allen, Lamarr Houston and Willie Young and the selection of tackles Ego Ferguson and Will Sutton in the second and third rounds of the draft.

"We're extremely excited about the competitive balance of that group, the players we've brought in through free agency and the draft, and the street free agents that we've brought in," Emery said.

When the Bears hit the practice field for the first time Friday, starting jobs will be up for grabs at two linebacker positions with D.J. Williams, Shea McClellin, Jonathan Bostic and Khaseem Greene the leading candidates.

"We've said numerous times that Lance Briggs is the only declared starter," Emery said. "The rest of the group is going to fight it out among themselves. There are quality athletes there. They all can play various roles in different situations; in sub situations versus run or pass personnel or all three downs. Some rush better, some cover better."

The depth chart is even more unsettled at safety, where newcomers will compete for the two starting jobs. During the offseason the Bears signed Ryan Mundy, Adrian Wilson, M.D. Jennings and Danny McCray in free agency and chose Brock Vereen in the fourth round of the draft.

The Bears announced Wednesday that Chris Conte, last year's starting free safety, will open training camp on the physical unable to perform (PUP) list after undergoing offseason shoulder surgery. Conte is expected to begin practicing sometime after the Aug. 8 preseason opener.

The Bears intend to move their safeties around in practice and the preseason and will start the two best players regardless of whether they've been working at the free or strong spots.

"The positions are essentially interchangeable," said coach Marc Trestman. "We can make them both work, so we want to find the best two guys. Whoever those two guys are within the framework of our defense is what we're looking to do."

On the offensive side of the ball, all 11 starters return from a unit that last season helped the Bears rank second in the NFL in scoring and set team records with 6,109 total yards, 4,450 passing yards, 32 passing touchdowns, a 96.9 passer rating and 344 first downs.

But the top reserve spot at virtually every position is wide open, highlighted by what promises to be an intriguing battle for the No. 2 quarterback job. Jordan Palmer will get the first opportunity, but Jimmy Clausen and rookie sixth-round pick David Fales will make it a three-horse race.

"It's going to start with Jordan and we feel really good about Jimmy and we felt really good about David's performance as well," Trestman said. "So we're just going to work at it like that. We're going to give Jordan the first shot; he's been here the longest. Jimmy Clausen has the most experience, so we're going to work him in there. We're going to continue to provide David with opportunity throughout camp to play and perform not only in practice, but in the games.

"It will be an ongoing process day-to-day, and we don't have to make a decision for quite some time. We'll get a chance to see a lot of plays in practice and certainly the preseason games as well. There will be opportunity for each of them to get some playing time."