Jon Meades has been ruled out until the New Year after the midfielder’s ankle operation was not as simple as expected.
The former AFC Wimbledon man went under the knife on Tuesday to repair damaged ligaments, but once the injury was opened up surgeons discovered more problems.
A disappointed U’s boss Chris Wilder said: “They had a look inside and there were a few complications so they had to do a bit more work than they thought was needed.
“That’s going to be a big blow for Jon.
“He came in and was an exciting signing for us, but his season hasn’t started and it possibly won’t until well into the New Year.”
It will take three months for the 21-year-old to recover from the procedure, at which stage he will only be able to begin jogging again.
The setback continues a nightmare time for Meades, who signed in the summer but suffered the injury during a pre-season game against Coventry City in July.
An operation was initially ruled out after the Welshman was sent for a scan, but the recovery was derailed when he felt pain while running earlier this month.
Meades is the only senior United player out with a long-term injury.
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