A decision over whether Michael Vaughan should undergo further knee surgery will be taken at a top-level meeting on Monday when the England captain will discuss his future treatment with England Test physio Kirk Russell, and Yorkshire physios Wayne Morton and Scott McAllister, writes David Warner.

Vaughan's knee condition has worsened over the past few days at Arundel and he has been ruled out of Yorkshire's final C&G Trophy North Conference match against Worcestershire at New Road tomorrow.

McAllister said: "Michael's rehab programme seems to have suffered a setback and we will have to decide whether he needs a longer period of strengthening his knee or if some other course of action is required.

"A fourth operation on his knee is a possibility but at this stage nothing has been set in stone and the situation needs to be carefully assessed."

If Vaughan is forced to have an operation to safeguard his career, he would miss the remainder of this season both with Yorkshire and England and there would be a big question mark over his recovery in time for this winter's Ashes series in Australia.

Vaughan was again unable to take the field for Yorkshire at Arundel yesterday and concern is mounting over his knee. If he does decide on an operation, it will be sooner rather than later and an announcement could be made early next week.

Rumour was rife among Yorkshire fans at Arundel that Vaughan was already set for an operation but that stage does not yet appear to have been reached.

At the moment neither Vaughan nor England wish to speak openly about the situation but it appears clear something positive has to happen soon because he is further away from full fitness than he was a few weeks' ago.

Yorkshire (from): White, Wood, Sayers, Lumb, McGrath, Gale, Gilbert, Brophy, Dawson, Ajmal Shahzad, Thornicroft, Claydon, Patterson.