Stoops said the issue was detected before practices began last week so nothing has been damaged further. But Stoops also had no details on when Ward will be able to get back onto the field.
"We're unsure where that will lead," Stoops said. "We're uncertain right now where that's going to be."
It's another obstacle to overcome for Ward, who hasn't played in a regular season game since his junior year of high school.
He was the No. 1-ranked prospect in the state despite not being able to play because of transfer eligibility issues.
Ward enrolled early to get a head start at OU but that didn't pan out, either. Issues with the NCAA kept Ward from being able to practice with the team until late in the spring. Ward barely had any time with the team before April's spring game although Ward did have quality playing time in the game.
Another concern on the defensive line was provided by a tweet by the official Oklahoma football Twitter account. The tweet was an Instagram video hyping up freshman running back Keith Ford running through an OU defensive lineman.
That's the good part to know Ford can come in and produce. The bad part of that equation for OU fans is the defensive lineman was defensive tackle Jordan Phillips.
Phillips is expected to be a vital part of OU's presence in the middle. Bob Stoops downplayed the significance of the video Monday, saying it was just one play and not to read too much into it. But with OU already having so many questions with the front seven, all it has done is add fuel to the fire.
Monday was OU's first practice with pads and Stoops said the good thing was nobody was injured during the drill or practice.