Ottawa will be without a second top-six forward for the remainder of its first-round playoff series against the Penguins. Second-line winger Milan Michalek left Wednesday during his team's 5-4 win in Game 1 with what was diagnosed as a full tear of the anterior cruciate ligament in his left knee.

The Senators already were without winger Alexei Kovalev, who also has an ACL injury. Both face offseason surgery.

Michalek had been playing with a brace because the ligament was already partially torn.

Winger Ryan Shannon, who has been a healthy scratch, is expected to join the Senators' lineup for Game 2 tonight at Mellon Arena.

"It's my opportunity to play solid minutes," said Shannon, who had five goals and 16 points in 66 games this season.

Before Game 1, the Penguins had faced Ottawa once since Dec. 23, and some of the built-in animosity that would be present from the first shift of a best-of-seven against, say, Philadelphia, was not evident Wednesday.

Penguins center Jordan Staal, though, figures that will change for Game 2.

"We haven't played that team in a while, and we maybe lost that hatred for them, stuff like that," he said Thursday. "I think we'll have that back in our game [tonight]."

Coach Dan Bylsma seems to be counting on that after Ottawa played Game 1 with an intensity and attention to detail that exceeded that of his team.

"The desperation level and the urgency level, [the Senators] were better in that department," Bylsma said. "They played exactly how we expected, what their game plan was. They were very good in that regard.

"We have to get to that right now. If them beating us in our building in Game 1, that hatred and that desperation had better be enough right now to bring to Game 2, and be ready to get to our game.

"We should have it right now with how they played, and how they played against us."

Penguins captain Sidney Crosby couldn't agree more.

"If anything, last game should motivate us even more," he said. "We hadn't played Ottawa for a long time. We have a history with them in the playoffs. I think that element of not liking them wasn't really there maybe enough because of the long period it's been since we've played them, but that's definitely there now."

Backup goalie Brent Johnson sat out the Penguins' practice because of what Bylsma described as "flu-like symptoms."

Johnson's status for Game 2 is not known, but the Penguins are taking no chances. They recalled first-year pro Brad Thiessen from Wilkes-Barre/Scranton.

Thiessen, a former Northeastern University star, was 14-14-1 with a team-best goals-against average of 2.45 with the Baby Penguins.

Winger Chris Kunitz was something of a surprise addition to the Penguins' lineup for Game 1. He had missed the last four games of the regular season because of a shoulder injury and had not practiced on a top-four line, including that day at the morning skate.

"Just the time between games that I had helped me get to a certain point where I felt a lot better," Kunitz said. "There are parts of my game I need to get back and do things -- go out there and try to be a physical presence and control the puck a little more."

He skated in his usual spot, with Crosby and Bill Guerin, piling up three shots and tying for a team-best five hits.

Off-day line combinations do not necessarily have much significance -- heck, Bylsma did not stick with his forward groupings at the Wednesday morning skate for the game that night -- but there were a couple of noteworthy changes during practice.

Pascal Dupuis replaced Ruslan Fedotenko on the No. 2 line with Evgeni Malkin and Alexei Ponikarovsky, and Mike Rupp, a healthy scratch Wednesday, skated on the fourth line with Max Talbot and Craig Adams.

Rupp is 6 feet 5, 230 pounds and can be an effective forechecker, something the Penguins need to help them to get play into the Senators' end and keep it there.

"Putting pucks behind them in the neutral zone and on the forecheck, making them go back and feel that presence wears on you, mentally and physically," Bylsma said. "There's an execution part to that, and also a physical aspect to that.

"He's created offense, zone time, big hits, begin that guy with speed through the neutral zone when pucks are behind the defense, then crashing in there and being a big body."

Tonight marks the first game that could be the last at Mellon Arena. Ottawa would have to complete a four-game sweep, though, to make it so. ... Each team practiced for about 45 minutes. ... Ottawa winger and captain Daniel Alfredsson was given a day of rest.

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