It is not difficult for Buffalo coach Lindy Ruff to recall the prowess of the Penguins when their top three centers are playing.
"I don't forget," he said. "I know what they're like."
That's more because of impact than recent memory.
Center Evgeni Malkin sat out the game Saturday night at Consol Energy Center against the Sabres. It was the third game in the past four he has missed because of soreness in his surgically repaired right knee. He had two assists Thursday in the Penguins' overtime loss against Washington but has not been on the ice since.
Penguins coach Dan Byslma indicated the absence against Buffalo was precautionary.
Top center and captain Sidney Crosby is taking contact in practice in his comeback from a concussion, but it is not known when he will be cleared to return to the lineup.
Crosby missed the second half of last season, and Malkin played once after Jan. 18, not at all after Feb. 4.
That leaves center Jordan Staal, who missed the first 40 games last season because of foot and hand injuries.
Those three played in just two games together in 2010-11 -- Jan. 1 and Jan. 5.
Perhaps sooner than later, the three again will be in the same lineup.
"It's something that the league is going to welcome; I'm not going to welcome it when it's all back together," Ruff said. "We know what they can do, how dangerous they can be and how good a team they were when they were in the lineup together."
Not that Ruff thinks the Penguins are deficient without Crosby and Malkin. Before Saturday night, the Penguins were 20-11-4 without those two, dating to when Crosby was diagnosed with a concussion.
"Oh, very dangerous," Ruff said.
"They're a hard-working, competitive team. They're getting some goal-scoring from different areas that makes them dangerous."
Defenseman Brooks Orpik has not played this season after having summer abdominal surgery, but is skating separately.
"He was pushing it pretty hard," Bylsma said of Orpik's session Saturday.
That means that the Penguins' contingent of alternate captains also has had a tough time being in the same game.
Before last season, Bylsma designated Malkin a full-time alternate, with Orpik wearing an "A" on the road and Staal wearing it at home.
Winger Chris Kunitz and defenseman Paul Martin have topped the list of fill-ins.
Center Dustin Jeffrey, who is on injured reserve but has been cleared for contact as he comes back from knee surgery, skated before the game-day skate, even though he has practiced with the Penguins at times.
"He's getting better and better, stronger and stronger," Bylsma said.
Crosby took Malkin's spot in the game-day skate, but Mark Letestu, a healthy scratch Thursday night, took Malkin's spot for the game. The Penguins' only healthy scratch was winger Steve MacIntyre. ... Buffalo's scratches were forwards Matt Ellis and Jochen Hecht (concussion) and defenseman Mike Weber (from Seneca Valley High School). ... The Penguins wore their dark blue alternate jerseys for the first time this season.
For much more on the Penguins, read the Pens Plus blog with Dave Molinari and Shelly Anderson at www.post-gazette.com/plus . Shelly Anderson: firstname.lastname@example.org , 412-263-1721 and Twitter @pgshelly .