BOSTON -- Patrice Bergeron returned to Bruins practice Monday morning for the first time since suffering a mild concussion in Game 4 of the Eastern Conference semifinals against the Philadelphia Flyers on May 6.

It was the third consecutive day Bergeron has skated (and his first day with his teammates), but coach Claude Julien would not give a timetable on the assistant captain's return to the lineup.

"As I said the other day, we're going through the protocol of what he has to go through," Julien said. "There's not much more to update you guys on except that I think, when he is ready to go, I think you guys will know it.

"It's just something that you can't predict, how quickly, or how slow it's going to be. It's just one of those situations where, right now, you see him going through what you saw him going through today's skating. But that's protocol, and right now, we're not ready to make any comments because he's just going through those stages."

When pressed further and asked if he's ruling Bergeron out for Game 2 on Tuesday, Julien said: "No comments."

According to a league source, though, the Bruins have not ruled out Bergeron for Tuesday's Game 2, but it will depend on how he feels on game day.

"Literally day to day right now," said the source, who acknowledged that Thursday's Game 3 in Tampa Bay was probably more likely for Bergeron's return.

After Game 1, Lightning coach Guy Boucher said he wouldn't be surprised if Bergeron was back in time for Game 2 on Tuesday. Since Bergeron practiced with the Bruins Monday morning, it gives Boucher even more reason to believe Bergeron will be back.

"I think that Bergeron, we know how important he is to the team. He's a great player. He's a great individual," Boucher said. "And that usually has a tendency to uplift your team in terms of confidence, and we know the impact he's got on the faceoff. So obviously his team's going to start with the puck a lot more often.

"It changes a lot of things in terms of the way the game is going to develop. So we're expecting him to be there for the opening faceoff, and if he's not, which I highly doubt, I think he's going to be there. It just makes it way harder. So they said they're coming out with their 'A' game and they're coming out with him. I'm sure [goalie] Tim Thomas is going to be at his best, and right now we're expecting Boston to come out flawless. So if we don't play a flawless game, forget it."

Bergeron spent more than an hour on the ice Monday morning. He skated for 30 minutes on his own with the team's strength and conditioning coach John Whitesides -- working on stops and starts, passing and shooting drills before joining the team's early work on special teams. Once Julien blew the whistle to begin the full practice, Bergeron remained on the ice for another 26 minutes before exiting. He also participated in light contact drills.

"It's good to see him and hopefully we get him back. He's a great player and it's definitely nice for everyone to see him out there and skating so well," said Bruins forward Nathan Horton. "He looked great out there today. As you can tell, he stays in really good shape."