The Vikings announced Wednesday night that coach Mike Zimmer needed emergency eye surgery that could cause him to miss Thursday night's game.

The surgery, which was to take place late Wednesday night, was the third for the third-year head coach this month. The previous two were on Nov. 1 and Nov. 8.

"His status for coaching [Thursday's] game is uncertain," General Manager Rick Spielman said in a statement. "I have met with the coaches and players, and we have a contingency plan in place if Mike is unable to coach against Dallas."

According to a team source, Zimmer had been scheduled to undergo a third surgery Friday.

The Vikings say they will provide an update on his health Thursday morning. Kickoff for their game against the Cowboys at U.S. Bank Stadium is 7:25 p.m.

Zimmer, 60, first underwent a procedure to fix a torn retina in his right eye Nov. 1, a day after scratching it during a loss to the Chicago Bears. Edina-based opthalmologists Dr. David Williams and Dr. Scott Sanderson performed that procedure, Zimmer said, and he was back at Winter Park later that afternoon.

"They said if you don't take care of those things that you have a possibility of going blind," said Zimmer, wearing sunglasses that day.

A week later, Zimmer revealed that he had "another thing done" and was "OK."

In the event that Zimmer is unavailable to coach Thursday night against the Cowboys, the Vikings, who have lost five of their past six games to fall to 6-5, have a pair of former NFL head coaches on staff in interim offensive coordinator Pat Shurmur and offensive line coach Tony Sparano.

Shurmer was hired to coach tight ends but his head coaching experience always made a bigger role a possibility. He'd coached the Browns for two losing seasons from 2013-15. He was the interim head coach for one game in Philadelphia last season, where he'd been the offensive coordinator. He was also the offensive coordinator previously in St. Louis. When Norv Turner resigned abruptly, Shurmur inherited the coordinator duties.

Sparano took over as the Dolphins head coach in 2008 one year after they'd won just one game and finished 11-5 en route to earning NFL Coach of the Year honors.

He was promoted to Raiders interim head coach during the 2014 season.

If Zimmer is unable to coach against the Cowboys, the Vikings are positioned well with an experienced staff to stand in short-term. Still, pressed into emergency action against the best team in the NFC would be a tall challenge for either Sparano or Shurmur, and perhaps no easier for Zimmer a day after undergoing eye surgery.