Stoltz will undergo an MRI today, but Arkansas assistant athletic trainer Eric Linson is not optimistic about the results.
"He most likely tore his ACL and got an MCL sprain," Linson said. "We're going to do an MRI (today), but it's probably going to confirm that suspicion."
Stoltz, who rejoined the Razorbacks this spring after missing last season because of personal issues, injured his knee during a team drill inside the Walker Pavilion.
"I hope he didn't tear his ACL," Arkansas coach Houston Nutt said. "He stepped wrong or pushed off wrong or something, and it looked like there might have been a little pop in there."
Stoltz will be a junior in the fall, and if the Little Rock native is unable to return next season, he would have at least more year of eligibility.
However, his injury further weakens Arkansas' already thin linebacker core.
Middle linebacker Weston Dacus continues to be held out of practice because of a mild concussion.
Meanwhile, sophomore Freddie Fairchild, who tore his ACL in the second game of last season, has been limited in what he can do this spring. He was originally dressed out to participate in Tuesday's practice, but coaches decided to hold him out as a precaution.
Earlier in the day, starting defensive tackle Marcus Harrison had surgery to repair a torn ACL in his left knee. The senior suffered the injury in the first week of spring practice.
"Marcus Harrison had successful surgery today on his ACL," Nutt said. "... We're glad that that is over with, and now he can start the rehab."
Stoltz Suffers Possible Torn ACL, MRI Today
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