Stefan Frei injured, departs in ambulance at end of Sounders-Crew draw | OneFootball

Stefan Frei departed Lumen Field in an ambulance at the end of a 1-1 draw between the Seattle Sounders and Columbus Crew after a knee-to-head collision during a set-piece situation.

Amar Sejdic was the Crew player involved. There appeared to be zero malice involved, the two players simply coming together as a result of Diego Rossi's outswinging diagonal ball on a late Columbus free kick.

Frei appeared to briefly lose consciousness during the sequence, but he was aware and responsive by the time he was loaded into the ambulance, said Sounders manager Brian Schmetzer.

"Stefan is being evaluated for a head and neck injury," Schmetzer said, per the Sounders' X (formerly Twitter) account. "He got hit pretty hard. We're in the early stages of that evaluation. As soon as we get a definitive, a real good clarity on the extent of the injury, we'll give you more. I don't want to speculate."He is going to the hospital, but he is fine. He was alert when he was loaded onto the ambulance … I'm very happy for our medical staff because they did a good job to be careful. We can't underestimate that type of stuff."

The collision occurred in the eighth minute of second-half stoppage time. After a stoppage of several minutes, managers Brian Schmetzer and Wilfried Nancy appeared to jointly convince referee Ismir Pekmic to blow the final whistle rather than resume the match with a Columbus corner.

The sequence was reminiscent of an earlier incident involving U.S. men's national team center back Walker Zimmermann in Nashville SC's match at Charlotte on April 5. Zimmerman was able to check out of the hospital the same night, but the impact of the injury lingered for several weeks. He made his MLS return on May 24 and is now part of the USMNT Gold Cup contingent.