Initially, Virginia cornerback Demetrious Nicholson assumed the nagging twinge in his foot had to be normal. This, he figured, was a challenge one must overcome when returning from a turf-toe injury.

So the senior grinded through the final spring practice of his career in April, hoping to show defensive coordinator Jon Tenuta that he was near full strength again. Except the throbs of discomfort worsened.

“It’s unexplainable,” freshman defensive tackle Andrew Brown said. “It’s just a bad pain shooting through the bottom of your foot.”

Nicholson and Brown have both been relegated to the sideline for team drills during the opening practices of Virginia’s preseason this week, recovering from turf-toe injuries that have become studies in how to rehabilitate an unpredictable ailment.

Sometimes players can return from turf toe, a sprain of the ligament in the big toe, in a matter of days. For others, it takes weeks. Nicholson, who suffered his injury in a loss to Ball State last October, just passed the 10-month mark.

Nicholson only began running again on the field two weeks ago after team doctors decided he should undergo surgery in the spring. He confirmed Tuesday that the procedure was performed on May 1.

“It got better, but I believe coming back and trying to push through it probably made it worse,” said Nicholson, who had started 30 consecutive games for Virginia before this injury. “They actually found a cyst in it that they didn’t know [about].”

With Nicholson out, Virginia has moved senior Brandon Phelps (Damascus) from safety to cornerback alongside starter Maurice Canady. Senior DreQuan Hoskey and sophomore Tim Harris are also options in the defensive backfield going forward.

Nicholson still expects to be ready for Virginia’s season opener against UCLA, but it’s unclear at this point how close he is to returning to action. Coach Mike London said before Tuesday’s practice that Nicholson’s absence through two days of training camp was more about conditioning after being on the mend so long and that doctors have already cleared him.

A few hours later, though, Nicholson noted, “Whenever I go back to the doctor and he fully clear me, I’ll be ready to go.”

It seems, however, that Nicholson’s rocky recovery has convinced Virginia to be more cautious with Brown, who underwent surgery on his right toe following the first week of spring practice. Considered the top defensive tackle recruit in the country last year, Brown grew up in the same Virginia Beach youth football circles as Nicholson and said rehabbing from similar injuries has provided motivation and guidance.

“I just keep reminding myself over and over again, ‘You can’t rush yourself back,’ because if I rush myself back I’m just going to hurt myself again,” Brown said. “They just don’t want to rush me back into everything so fast.”

New defensive line coach Jappy Oliver said he still expects the 305-pound Brown to be a major contributor this season. Unlike Nicholson, Brown has been participating in individual drills and appears he could play in a game if there were one this week.