



The Swede, who joined the Wearside club last Thursday from Valencia, in a deal worth just under £4m, was told that space travel would invalidate his contract.

The 30-year-old midfielder, who is already being dubbed 'The Spaceman', is an important acquisition in Sunderland's attempts to strengthen their Premiership squad.

But the club's management, including manager Peter Reid, told Schwarz that any potential flights into space would not be tolerated, before the contracts were sealed on the four year transfer.

Speaking on BBC Radio 5 Live, Sunderland's chief executive, John Fickling, said: "One of Schwarz's advisers has, indeed, got one of the places on the commercial flights.

"And we were worried that he may wish to take Stefan along with him. So we thought we'd better get things tied up now rather than at the time of the flight.

"It was a reasonable request. We would normally get insurance cover for the player throughout the length of his contract. And like a lot of insurance policies there are certain exclusions, such as dangerous activities.

"At the end of the day we are protecting the club, really. It was a little bit of a light-hearted moment during protracted negotiations.

"But one day it could become be quite acceptable to put such clauses in various contracts."