WES Thomas remains sidelined for Oxford United, with head coach Michael Appleton admitting they are unsure about the cause of his recurring calf injuries.

The problem resurfaced a fortnight ago against Bradford City and the striker will miss tomorrow’s clash with Millwall in Sky Bet League One.

Thomas increased his workload with the U’s medical staff yesterday as he works back to fitness, but Appleton revealed they were no nearer getting to the root of the issue.

The head coach said: “I don’t know if it’s down to (a lack of) strength or fatigue, but ultimately for whatever reason he’s not been right.”

There is better news over Ryan Ledson, who played an hour without any issue for the development side on Tuesday.

While tomorrow’s game comes too soon, Appleton believes the former Everton youngster could feature against Merstham in the Emirates FA Cup first round.

He said: “When you have a hamstring injury you get a pretty good indication of where you’re at, whereas with knees it’s about confidence going into tackles.

“I think next weekend Ryan can be involved a bit more.”