Rafiq (extreme left) was part of Yorkshire's win over Notts

Durham's Twenty20 quarter-final with Yorkshire was postponed after Tykes spinner Azeem Rafiq was alleged to be an ineligible player.

Seven thousand fans were gathered at the Riverside ready for the 1740 BST start when the news filtered through.

The England and Wales Cricket Board is investigating the matter and asked that the match be played at a later date.

Rafiq, 17, made his Yorkshire debut in their final group match against Notts, which a panel may order to be replayed.

Both teams were preparing for Monday's quarter-final, unaware of what was to follow until little more than an hour before the scheduled start.

It emerged that questions had been raised about Rafiq's British nationality and that he was only eligible to play at levels below the first team.

An ECB spokesman said: "ECB made it clear to both counties that in view of the alleged ineligibility of Azeem Rafiq, it was possible the panel could order the replay of any match or matches which could affect any quarter-final.

606: DEBATE Tell us what you think about the postponement

"The ECB are convening a meeting of the panel as a matter of urgency so that any relevant matches will be played before Twenty20 finals day at Southampton on 26 July," an ECB statement confirmed.

ECB chief executive David Collier announced that a meeting had been pencilled in for Thursday.

The match in question, in which Rafiq, a former England Under-15 captain, took 0-18 from two overs in a victory against Notts at Trent Bridge, was played back on 27 June.

There had been speculation that the ECB were made aware of the registration problem regarding Rafiq within days of that fixture, but Collier insisted they had only discovered the facts on Monday morning.

Confusion reigns on the Yorkshire balcony at the Riverside

"I don't think we could have done any more than what we've been doing," he said.

"The worst would have been to just ignore it and act as though nothing had happened and let the game go ahead with the knowledge that the game may well have to be replayed.

"There was no registration of the player right from the outset - that was the key problem. There were several severe complications in this case, but the bottom line is the player was not registered to play in first-class cricket."

Had Notts won that game, they would have qualified ahead of Yorkshire.

Yorkshire coach Martyn Moxon admitted: "I have no idea what the outcome will be. It is a very complicated set of rules and regulations. He was on our list of players but as an academy player rather than a full-time contract player.

"He needed to have signed a paper saying he agreed to the regulations of the ECB but that piece of paper has been failed to be signed.

"Since then it would appear his status within the country appears to be in question.

"He has a permit allowing him to remain and work in this country indefinitely but his status in the first team brings him under ICC regulations and under those he does not have the relevant qualifications."

It's very complicated, very sad for the game and very sad for the competition Durham coach Geoff Cook

"Through no fault of our own, and without feeling too sorry for ourselves, we seem to be suffering all round," he said.

"We have to wait until the process is sorted out between Nottinghamshire, Yorkshire and, I think, Glamorgan, and then we will expect to play the winners here at the Riverside.

"The whole thing is a very unsatisfactory situation. It's very complicated, very sad for the game and very sad for the competition. I feel very sorry for the lad involved."