Mark Eaton did not return to the Penguins' lineup yesterday with a multiple-point game, or a series of crushing checks.

Fact is, nothing about his personal linescore from the Penguins' 5-0 victory against Boston at Mellon Arena --17 minutes, 43 seconds of ice time, two blocked shots, a hit, the second assist on Ryan Malone's short-handed goal and a plus-minus rating of plus-1 -- was spectacular.

Then again, not much about Eaton's game is. The Penguins count on him for solid defensive play, and Eaton produced that while working alongside Rob Scuderi in even-strength and short-handed situations in his comeback from a sprained knee that forced him to sit out 12 games.

"There was a little rust factor, but I felt pretty good, felt strong," Eaton said.

Eaton, who replaced Alain Nasreddine in the lineup, showed few signs of his time off, and made a heady play while killing a slashing penalty to Sergei Gonchar early in the second period. When goalie Marc-Andre Fleury lost sight of a loose puck in the crease, Eaton backhanded it between his own legs and out of danger.

"Any time you're off for an extended period of time, there's a little adjustment to get [used] to the speed of the game and making plays out there," he said. "I just look forward to getting better."

Magic number

The Penguins' magic number for clinching their first playoff berth since 2001 is three.

Probably.

Any combination of points that they earn and/or the New York Islanders fail to earn that adds up to three will guarantee that the Penguins, who have 96, will finish ahead of New York, which would end up with 98 if it wins its remaining seven games.

However, if that total is reached strictly by the Islanders losing three points, Montreal theoretically would be able to remain alive, because the Canadiens can earn up to 96 points and still could overtake the Penguins in the victories tiebreaker, where the Penguins hold a 43-39 edge.

As soon as the Penguins pick up one more point -- or Montreal fails to get one -- they will be assured of finishing ahead of the Canadiens.

The Penguins' victory yesterday guaranteed that Toronto, which could finish with 96 points, can do no better than to match their total of 43, and the Penguins have an insurmountable 3-0 lead in the second tiebreaker, head-to-head competition.

Bottom line: If the Penguins win in Washington tomorrow and the Islanders fail to defeat New Jersey at Nassau Coliseum, the obvious becomes official, and the Penguins are in.

No quit in Ference

The Bruins didn't just get a defenseman when they acquired ex-Penguin Andrew Ference from Calgary in February. They got a conscience.

And even though mathematical elimination from playoff contention is pretty much imminent, Ference told the Boston Herald that it's imperative for the team to establish an identity -- and accountability -- during the balance of this season.

"We have a lot of new guys and a lot of young guys, and the culture that you create around the team and the identity that this team is going to have over the next couple of years, it's determined in the first few months," he said.

"Part of the culture I've experienced with successful teams is one where there is emotion and there is honesty. You're looking each other in the eye after wins and losses and not wondering if your teammate did all he could that day.

"The argument for these [remaining] games being a crossroads can be made because this is when true character shows. ... Teams with character play when they are down, 7-0, when they are just on the fringe of that playoff spot. That's when they still show up and show what they're made of."

Slap shots

In addition to Nasreddine, the Penguins scratched forwards Ronald Petrovicky, Chris Thorburn and Nils Ekman and defenseman Joel Kwiatkowski. ... Yesterday's game attracted a standing-room crowd of 17,132, the Penguins' 21st sellout in the past 23 dates and their 28th of the season. ... Boston defenseman Mark Stuart was recalled from the Bruins' AHL affiliate Friday, forcing him to miss the Providence Bruins' Mark Stuart bobblehead promotion the next night.