Celtic are still hopeful of landing Thomas Gravesen before the transfer window closes on Thursday night.

The Real Madrid midfielder flew to Glasgow yesterday for a medical and to discuss personal terms.

But the club insist negotiations with the player and his agent John Sivebaek will continue over the phone although Newcastle could try to gazump Celtic's deal.

A Celtic spokesman said: "Talks are ongoing."

Gravesen was allowed to leave Denmark's training camp to fly to Scotland for talks but has returned to prepare for Friday's friendly against Portugal and next week's Euro 2008 qualifier in Iceland.

The arrival of Gravesen at Parkhead would pave the way for Stilian Petrov's switch to Aston Villa.

Portsmouth manager Harry Redknapp claimed the Bulgarian was set to join up with former boss Martin O'Neill. But Petrov's agent Tony McGill said: "Stilian has not signed for anybody.

"I am working on other projects now," he said. "I have spent too much time on this now. If it happens somebody is going to have to do an awful lot of work and it's not going to be me."  PA