RICKY Holmes is a doubt for Oxford United's trip to Portsmouth on Saturday.

The 31-year-old has managed a back problem for years, which requires regular injections.

The latest was earlier this week and it typically takes a while to settle down, so United are monitoring the situation.

It would be a blow if Holmes missed out, having made a big impact on his U's debut last weekend.

United head coach Karl Robinson said: "Everyone knows he’s had a stiff back and had an injection on Wednesday.

"We’ll wait and see how that settles down over the next 48 hours.

"He certainly won’t be 100 per cent fit if he does play, we’ll have to wait and see."

James Henry was also not training with the squad at Thame United's ASM Stadium this morning, while he nurses a dead leg picked up in Tuesday's 2-0 win over Coventry City.