Oxford have rejected an offer for James Constable from League Two rivals Bristol Rovers.
The 27-year-old bagged 11 goals in 40 league appearances for the U's last season, topping their scoring charts for a fourth successive campaign and taking his tally to 74 goals in 166 outings.
But Oxford have knocked back Rovers' attempt to secure his services.
Chairman Kelvin Thomas told United's official website: "Over the past season James has attracted interest from a variety of clubs and further interest is not really a surprise.
"We have received a formal offer for James from Bristol Rovers but we have turned it down."