Chivas USA midfielder Thomas McNamara will undergo surgery to repair a torn right ACL and medial meniscus tear, the club announced Friday, leaving one of the league’s brightest rookie prospects on the shelf for an undisclosed amount of time.

McNamara, 23, suffered the injury during Chivas USA’s 1-1 draw at the Portland Timbers last Saturday (above). The surgery will take place at a date yet to be determined and additional information on the prognosis will be provided at a later time, according to the club, but most ACL recoveries last between 6-12 months depending on the player.

Drafted in the second round of the MLS SuperDraft in January after a standout career at Clemson, McNamara started each of Chivas USA’s first six games of the season and scored a goal in the team’s season-opening win over the Chicago Fire.