Milan Michalek, the Senators' leading goal scorer, won't be in the lineup when Ottawa faces off against the Florida Panthers on Saturday night at Scotiabank Place (Getty Images).

Not all that long ago they formed a rather potent first-line trio for the Ottawa Senators.

But now Milan Michalek will join captain Daniel Alfredsson and No. 1 centre Jason Spezza as a spectator – at least for Saturday's matchup with the Florida Panthers (7 p.m., CBC, Team 1200) at Scotiabank Place and perhaps a little bit longer.

Senators head coach Cory Clouston confirmed today that Michalek, the Senators' top goal scorer, is sidelined with an upper-body injury he suffered on a hit by Capitals' Mike Green during the first period of Ottawa's 5-2 loss in Washington on Thursday night. Alfredsson (shoulder) and Spezza (knee) are still on the shelf with long-term injuries.

"It was our first line not too long ago," Clouston said in pondering life without Michalek, Alfredsson and Spezza. "We need other guys to step up. We need to simplify our game even more and just keep working hard and being positive.

"We’ve got a foundation laid that, if we stick with our systems and capitalize on our chances, we’ll be okay. But we’ve taken almost a hundred goals out of our lineup. But that’s still no excuse. We’ve still got to make the most of what we’ve got."

Clouston also said Michalek won't be with the team for at least the start of a five-game road trip that begins Sunday in Raleigh, N.C., against the Hurricanes (5 p.m., Rogers Sportsnet, Team 1200). Zack Smith and Martin St. Pierre have been summoned from the Senators' American Hockey League affiliate in Binghamton, N.Y., suggesting another lineup change is likely to be made against the Panthers.

While Michalek leads the Senators with 16 goals, his presence will be missed in other areas.

"When you lose a guy like Milan, it’s not just (that you’re) taking him out of the lineup," said Clouston. "He plays power play and he does a real good job on the penalty kill, so now you’re really forced to put guys in different roles and use them differently."

The 5-foot-9 St. Pierre, a native of nearby Embrun, Ont., has been an offensive standout all season for the B-Sens and has a team-leading 21 assists and 35 points. He's also been a leader on the power play, an area in which the Senators have struggled recently.

"We hope he can give us a little bit more offence and there may be some times when he’s going to see some power play (time)," Clouston said of St. Pierre, who has 35 games of previous National Hockey League experience with the Chicago Blackhawks and Boston Bruins. "I know being able to be a strong power-play guy in the American league is a little bit different than (doing it) in the NHL, but it’s a situation where we think he’s going to be able to help us out at times.

"And he’s going to have to. For him to be effective, he’s going to have to give us some creativity on the power play."

Smith, a 6-2, 210-pound forward from Maple Creek, Sask., brings an entirely different sort of game to the table.

"Zack hasn't produced maybe as much as we'd like offensively (in Binghamton), but he's played solid physically," said Clouston. "He's a big, strong guy that we really liked last year and he put up some numbers last year. He's still got that physical presence – he works hard and he's strong on the puck."

Around the boards

With a long road trip in sight, Clouston gave his players the full day off on Friday. They'll face Carolina, the Atlanta Thrashers, New York Rangers, Montreal Canadiens and Boston Bruins in a nine-day span starting Sunday ... Fewer than 3,500 tickets remain for Saturday's game ... St. Pierre was previously named to the Canadian team for the AHL All-Star Classic, set for Jan. 19 in Portland, Maine.