Atlanta United forward Josef Martinez has a torn ACL in his right knee, the club announced on Sunday.
Martinez was stretchered off in the second half of Atlanta's season-opening 2-1 victory over Nashville SC after a clumsy challenge from behind.
The date for the surgery has not been determined.
Martinez was named MLS MVP in 2018 with a record-breaking season in just his second year with Atlanta, scoring the most goals in league history with 31 goals in 34 games (since surpassed by Carlos Vela) on his way to the Golden Boot award and helping lead the team to MLS Cup final victory over the Portland Timbers.
The Venezuela international scored another 27 goals in 29 league matches in 2019, and began the 2020 season with two goals from two CONCACAF Champions League matches before suffering the injury on Saturday.
Atlanta United (1-0-0, 3 points) are back in action on Saturday for their home opener against FC Cincinnati.