WIth training camp underway and the NHL season rapidly approaching, Philadelphia Flyers coach Peter Laviolette has some decisions to make besides just putting together line combinations.

Sixteen skaters return from the team that pushed the Chicago Blackhawks to six games in the Stanley Cup finals just a few months ago. They will be joined by new forwards Bill Guerin, Nikolai Zherdev and Jody Shelley, and new defensemen Andrej Meszaros, Sean O'Donnell and Matt Walker.

That leaves 22 players battling to be among the 18 who will be on the ice on opening night Oct. 7 in Pittsburgh - though two or three more could be kept on the team as healthy scratches.

Forwards Zherdev, Mike Richards, Jeff Carter, Ville Leino, Danny Briere, Scott Hartnell and Claude Giroux are locks. So are defensemen Chris Pronger, Kimmo Timonen, Matt Carle, Braydon Coburn and Meszaros.

Here's a look at the defensemen on the bubble, and their chances of making the team. Tomorrow, we'll take a look at the forwards on the bubble.

 

Sean O'Donnell - O'Donnell turns 39 in the first week of the season, but he's still a solid player, especially considering the Flyers only need him to be their No. 6 defenseman. He's had a positive plus-minus in 12 of his 15 seasons, including the last eight. He won the Cup with Anaheim in 2007. After watching the bumbling Ryan Parent hold down the No. 6 spot for most of last season, Flyers fans should enjoy the veteran O'Donnell's steadiness. The only reasons he's on this list are his age, his one-year contract and the Flyers' depth on the blue line - all factors that mean he could be cut if he has a really poor preseason.

Matt Walker - Walker is the body the Flyers got in return when they dumped Simon Gagne's salary on Tampa Bay. The 30-year-old has had a positive plus-minus just twice in seven seasons, including a minus-11 last season. But he is at least a guy who has played 306 career games, which is nice to have as insurance on a team with three defensemen 36 or older (Pronger, Timonen and O'Donnell). So while his only shot at being in the lineup on opening night is likely an injury to someone else (Pronger is recovering from offseason surgery), he has a good chance to stay on as the seventh defenseman, a healthy scratch for most games but filling in when needed. One thing that might hurt him is his salary - Walker makes $1.7 million, according to capgeek.com, making him a candidate to be traded or waived if the Flyers choose to clear cap space for whatever reason.

Oskars Bartulis - For a rookie, Bartulis wasn't bad last year when he replaced Parent in the lineup after Game 1 of the Cup finals. The 23-year-old is promising and might play for a lot of other teams, but the Flyers are looking to win now, so they'd rather have a veteran such as O'Donnell or Walker in there. Barring a spectacular preseason, Bartulis is likely to spend this season in the minors with the Phantoms. But he remains a part of the Flyers' future and is also insurance for the Flyers' aging blue line this season.