PITTSBURGH — As he lay crumpled on the ice following a devastating hit by Penguins defenseman Brooks Orpik, Jonathan Toews uttered something apparently unprintable, stood up and skated off to the bench, clutching his left arm with his right. He sat on the bench, hunched over in pain a couple of times, then got up and left for the dressing room.

The question now is, when will he come back?

Already without one of the top offensive players in the world in Patrick Kane, the Hawks might have lost one of the most irreplaceable players in the world in Toews. He left the Hawks’ 4-1 loss to the Penguins Sunday night with about 6:30 left in the second period, and didn’t return with what the team termed an “upper-body injury.” There was no immediate word on the nature or extent of the injury.

So with less than two weeks until the end of the regular season, the Hawks’ 0-3 road trip and slip to third place in the Central Division isn’t even close to the biggest concern.

The hit came along the boards in the offensive zone, as Toews tried to chip the puck ahead to Marian Hossa. Just after he moved the puck, Toews was still crouched and still had his head down when Orpik came in and delivered a crushing blow. While he didn’t leave his feet until after contact was made, Orpik’s arm hit Toews in both the shoulder and the head at the same time. The league will look at what can fairly be deemed a borderline hit, but it didn’t appear that Toews’ head was the principal point of contact — the usual criterion for an illegal high hit.

Toews had taken a big hit from Orpik earlier in the period, and was slow to get up. Then, he collided with teammate Peter Regin on the ensuing line change, slamming his stick on the boards in frustration.

As for the game, it was another discouraging effort for the Hawks, who clinched a playoff spot Saturday night without playing a game, but fell to third place with Colorado’s latest victory. The Hawks and Avalanche are fighting for home-ice advantage in their likely first-round playoff series.

Kane, who was hurt on March 19 when Brenden Morrow fell on his left leg, is expected back in time for the playoffs. His absence has been felt offensively, particularly on the power play.

But Toews is one of the most indispensable non-goalies in the league, a significant factor at even strength, on the power play, and on the penalty kill. The Hawks also are thin up the middle — rookie Teuvo Teravainen moved up to top-line center after Toews’ injury. Other centers in the lineup are Michal Handzus (who didn’t play in the third period), Marcus Kruger and Peter Regin — quality role players and solid defensive presences, but not the elite offensive talent that Toews is.

This was a matchup of two teams looking to snap out of recent funks — each was 4-5-1 in its last 10 games. The Penguins got the jump early, and scored twice in 21 seconds midway through the first period thanks to Hawks defensive lapses — James Neal on a two-on-one, and Lee Stempniak immediately after.

The Hawks made it 2-1 when Sheldon Brookbank’s rising slap shot made it through an Andrew Shaw screen at 11:10 of the second. Corey Crawford made several big stops after that to keep the Hawks in it after that. Then came Toews’ injury. The Hawks didn’t retaliate on Orpik or anybody else, but ratcheted up their play in the third period — until Sidney Crosby scored on yet another two-on-one with 4:51 left to seal it. He added an empty-netter with 1:16 left.

Email: mlazerus@suntimes.com

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