Loft problem hampers Vale Doug Loft will miss Port Vale's clash with Oxford on Monday as Micky Adams' side bid to cement their place in an npower League Two automatic promotion spot. Vale are a mere three points behind leaders Gillingham heading into the weekend and their skipper has been instrumental in his side's impressive start. But he pulled up with a calf injury after 51 minutes of his team's 2-0 win at Exeter last week and is expected to miss more than a month of action. Teenage goalkeeper Sam Johnson is set to retain his place and make his league bow with Chris Neal still struggling with a groin strain. Johnson, 19, made an impressive debut in the midweek Johnstone's Paint Trophy penalty shootout win at Walsall where he saved three spot-kicks before scoring the winner himself. Johnny Mullins is set to return for Oxford. The defender was unavailable for the Johnstone's Paint Trophy win over Cheltenham on Tuesday but will regain his position in the back four after impressing in the goalless draw against Gillingham last weekend. Captain Jake Wright is also expected to come back into the defence while Andrew Whing provides another option after making his comeback from the bench against Cheltenham. Damian Batt is also back in the frame after picking up an injury against Gillingham. Lee Cox could return in midfield after making a quicker than expected recovery from a groin injury but Liam Davis (groin), JP Pittman, Michael Raynes (both hamstring) and Michael Duberry (neck) are still missing.