INDIANAPOLIS - It will be a challenging off-season for Minnesota Vikings Head Coach Mike Zimmer as he tries to sort out his embattled offensive line and come up with a solution at running back.

And then there's the matter of his eyesight.

Zimmer shared with reporters at the NFL Combine in Indianapolis Thursday morning that he has two additional surgeries scheduled for his badly compromised right eye. ESPN's Kevin Seifert reports that Zimmer says he hopes the procedures restore 50 percent of his current limited vision.

At this point Zimmer has already had four procedures on the eye after he suffered a detached retina just before the Vikings' Halloween game against the Chicago Bears. Making matters worse, doctors have told him the same problems could pop up in Zimmer's left eye, which so far has been unaffected.

The fifth procedure, to fix that detached right retina, is currently set for mid-April. The sixth will be scheduled for early summer.

Zimmer, like most of his fellow coaches, is making the media rounds at the combine. He spoke with PFT reporter Mike Florio live on Facebook about a number of topics, including the pending free agent status of running back Adrian Peterson and what he needs to improve on following a disappointing 2016-17 season.

"It's gone by long and quick," Zimmer quipped when Florio noted that the upcoming season will be Zimmer's fourth as Vikings Head Coach. "I was talking to Coach (Bill) Parcels the other day, I said 'you know coach, a lot of these coaches that get fired after year one or year two, they don't ever learn how to be, truly be a head coach.' So hopefully I'm learning by now."

Zimmer blamed the team's late season swoon on himself, saying that blaming injuries or anything else isn't his style. "I think it's a coach's job to take whoever he has... and get em' to play good and win games. And we didnn't do that at the end of the year."

The coach told Florio that trading for QB Sam Bradford was a good move, and said that in order to strengthen their relationship Zimmer may travel to Bradford's home in the offseason and get to know him a bit better. When asked about the future of Teddy Bridgewater, who suffered a knee injury that some feel could end his career, Zimmer only spoke of his affection for his young QB. "I love him as a person, I love him as a player, I just want him to get healthy," the coach insisted.

Peterson's future is a topic that everyone seems to be buzzing about. Zimmer was asked by reporters if he had begun ranking running backs at the combine to replace Peterson, who was told this week that the Vikings would not exercise his $18M option for 2017. Zimmer said he had heard this is an extremely strong class of college backs, but also would not commit to the idea Peterson is done with the Vikings. "We allow these guys to go out and see what their market value is," he insisted, referring to Peterson and others being allowed to test the open market. "I think if we treat these guys fairly there will be a lot of them that want to come back."