With their playoff hopes on the line, the San Jose Sharks hobble into critical Game 6

Top defenseman Erik Karlsson couldn’t finish the game because of a recurring lower body injury, while captain Joe Pavelski and second-leading scorer Tomas Hertl didn’t return after high hits, and winger Joonas Donskoi had his day cut short after taking a puck to the mouth.

As if the San Jose Sharks aren’t facing enough of a challenge after a 5-0 loss to the St. Louis Blues Sunday at the SAP Center, which put them in a 3-2 hole in the Western Conference final, they now may face an elimination game Tuesday in St. Louis with a depleted group.

The Sharks seemed to get a boost when Karlsson, a two-time Norris Trophy winner, was in the lineup Sunday. Karlsson suffered leg and groin injuries during the season and sat throughout Game 4’s third period with an apparent re-aggravation.

But his first-period turnover led directly to St. Louis’s first goal 5:50 into the game, and he played just three minutes in the second period before being shut down.

“Hindsight’s 20/20,” Sharks coach Peter DeBoer said. “We made that decision based on the reports we get from the player and the medical, and the report was he could play and get through the game. It’s easier to sit here and say now (that) sure, you have regrets.”

San Jose suffered another significant loss in the first period when Hertl, whose 10 playoff goals were the second-most on the team, took a shoulder to the head from Ivan Barbashev at center ice. He stayed down after the hit and played through the second period before he, too, missed the entire third period.