Defensive stalwart Axel Sjöberg was injured in extra time during the Colorado Rapids’ 1-0 loss to the New York Red Bulls Saturday afternoon. Sjöberg executed a slide tackle in the Rapids’ penalty area, effectively winning the ball and thwarting an attack but injured his left leg in the process.

After the slide, Sjöberg had difficulty standing, and when he finally climbed to his feet he struggled to put any weight whatsoever on his leg. The referee saw him, stopped the game and allowed the Rapids to make a sub. Sjöberg eventually hopped off of the field with minimal assistance, but was hesitant to put any weight on the leg.

The 2016 MLS Defender of the Year nominee and Rapids’ Defender of the Year was a big reason that the Rapids were one of the best defensive teams in the league last year. He started all games he played in and was named to the MLS Team of the Week twice. The 26-year-old, who celebrated his birthday three days ago, started 30 games at the center back position last year, so suffice it to say that the loss of the game may be the least of the team’s worries.

If Sjöberg misses any length of time, the Rapids have cause for concern. He is the leader and most vocal member of the back line, a role that will not be easily replaced. If out, Mastroeni’s best options are Bobby Burling or Mekeil Williams, both moves that would probably necessitate a shifting of positions on the back line.

There’s no word as of yet how serious the injury to Sjöberg is. The fact that he was able to get off the field under much of his own power is promising, but no one will know for sure until doctors get a chance to look at him. The Rapids will take on newly minted Minnesota FC next Saturday at home, with or without Sjöberg.