Arkansas athletic trainer Dean Weber said late Tuesday night that Monk had the latest surgery to remove loose particles in his knee.
"He had a couple of loose bodies and they were removed and he's recovering now," Weber said.
Weber said he couldn't give a timetable on when he thought the senior wide receiver might be able to return to the field.
But Arkansas sports information director Kevin Trainor said Tuesday night that it will likely be "Kentucky or beyond before Monk returns."
No. 21 Arkansas faces Kentucky on Sept. 22 in the third game of the season. Before then, the Razorbacks host Troy University in Saturday's season opener and play at Alabama on Sept. 15.
Monk underwent the first arthroscopic surgery on his right knee on Aug. 13. During the surgery, doctors repaired a small tear in the posterior horn of the lateral meniscus and removed pieces of articular cartilage.
Monk was expected to miss at least four to six weeks after undergoing the surgery earlier this month.
When asked if the second surgery could delay Monk's return to the field, Weber said, "It may some, sure. I don't know if you start back at square one."
Monk injured his knee during an Aug. 9 practice when he was hit hard from behind by free safety Michael Grant after catching a pass. The injury was originally believed to be a bone bruise.
Initially, Arkansas coach Houston Nutt thought Monk would only miss a few days of practice after an MRI came back negative. But doctors discovered during the first surgery that Monk's knee had suffered more damage than originally believed.
Monk was easily Arkansas' leading receiver last season, catching 50 passes for 962 yards and a school-record 11 touchdowns.
Clay Henry also contributed to this report.
Monk Undergoes Second Knee Surgery
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