The Sharks fought till the end, but they still fell short.

San Jose went into St. Louis on Tuesday hoping to conclude its road trip with a momentum-generating win over the reigning Stanley-Cup-champion Blues. Instead, the Sharks emerged with a 3-2 loss and now head back to the Bay Area having earned only five out of 10 possible points on the five-game trip.

While the missing points sure would be useful as San Jose attempts to jockey its way back into playoff position, they're not the death knell of the Sharks' season. But Logan Couture's apparent knee injury just might be.

Early in the second period, Couture awkwardly went into the boards after a collision with Blues defenseman Vince Dunn. The Sharks' captain immediately grabbed at his left knee and appeared to be in serious pain. He required assistance to get off the ice, was taken to San Jose's locker room and was ruled out for the remainder of the game.

The injury did not look good, and Couture was wearing a walking boot after the loss. Sharks interim head coach Bob Boughner informed the media that X-rays were taken and he was of the belief that, "they are negative." Boughner added that Couture will be reassessed again on Wednesday and that he doesn't think, "it will be anything too, too serious."

The fact that Couture flew back on the team plane is a promising sign. But until more information comes to light, San Jose will have a pit in its collective stomach.

Simply put, the Sharks cannot afford to lose Couture for an extended period of time. If they have any chance of qualifying for the playoffs, it's extremely hard to see them accomplishing that feat without arguably their best all-around player.

In addition to appearing in every game so far this season, Couture leads the Sharks with 36 points. He ranks fourth on the team with 14 goals and is tied for second with 22 assists. He plays in every situation, and only Evander Kane averages more ice time among all San Jose forwards.

Couture's first season as captain certainly hasn't been an easy one, but he has remained a vocal source of accountability for a team that thus far has needed to be held accountable. The Sharks can count on him to continue providing that quality regardless of how serious the injury is.

But if Couture misses any lengthy period of time, you can pretty much count San Jose out.