Martinez's father, Casey Martinez, wrote in an email to The Associated Press on Monday night that the senior quarterback has a "debilitating injury" near the ball of his left foot that could take until February or March to heal fully.
"Taylor's injury happened in week one and after several months of rehab we have discovered that the more he does on it the worse that it gets," Casey Martinez wrote. "Very, very unfortunate location and aggravating injury that can't be toughed out.
"This is a nightmare way to finish your college career, by getting this kind of injury in the first week of the season, which essentially has cost Taylor his whole senior season as well as many team and personal goals."
Casey Martinez wrote that he has spoken to a foot specialist who works with elite athletes but did not recall the medical term for his son's injury. Coach Bo Pelini originally called the injury a turf toe, but has described it as a sprain the past two weeks.
Taylor Martinez has not spoken to reporters since the Oct. 26 loss at Minnesota.
Asked at his Monday news conference about the possibility of Martinez playing again this season, Pelini said, "I don't know if the chances are real good."
Martinez has been limited to four games. He has had nagging injuries to his shoulder, hip and abdomen, but the injury to his left foot has been the main reason for his absences.
"We feel confident that Taylor will be 100 percent in late February or early March, as he has already been in continuous rehab since his injury," Casey Martinez wrote. "Right now he wants to just continue rehab and be there for his team anyway possible."
Martinez has been the starter since his freshman year. The senior holds career school records for total offense, yards passing and touchdown passes. Tommy Armstrong Jr. has started five games in Martinez's place.
Martinez missed three games, but returned for the game at Minnesota. He hasn't played since.
Why did he play against the Gophers if he wasn't healthy?
"Because he could tolerate the pain and compete at a level to execute the game plan, which he did," Casey Martinez wrote. "Playing and practicing on this injury unfortunately just seems to aggravate it, and Taylor was under the impression that he could just tough it out and maybe fight through the pain, which he realized isn't in the best interest of his long-term health."
Nebraska hosts Michigan State in a key Big Ten game on Saturday, and Armstrong will be under center again.
"I hate to speculate and make a bold statement that his college career is over," Casey Martinez said of Taylor, "although, as Bo stated, it doesn't look good."