Howard was a key member of Morecambe's side last season (Getty Images)

The former Swansea player goes straight into the team for the Blue Square Premier game with Grays on Saturday.

Howard was a key member of Morecambe's promotion-winning side last season and was their player of the year the previous term.

Oxford have transfer-listed six players including defender Alex Jeannin and are expected to sign more new faces soon.