Carlos Carvalhal has revealed how managing in Turkey gave him the resilience to cope with a Premier League relegation battle.

The Swansea City manager had to deal with jailings, an absent board and no pay during his spell at Besiktas – all of which helps keep his current tasks in some sort of perspective.

Carvalhal takes the Swans to Manchester United this weekend, where he will come face-to-face with compatriot Jose Mourinho, who he once studied during a week spent when his fellow Portuguese boss was at Chelsea.

But that was nothing as useful as the season Carvalhal was in charge of the Black Eagles of Besiktas in 2011. The 52-year-old had already gone through 13 clubs when he arrived in Istanbul, but it was at Besiktas where he learned how to manage.

“It wasn’t easy,” he says. “It was a different language in a different country, working with a staff that wasn’t mine, the previous manager was put in jail, the club was without a board, and no-one was being paid for four months.

“I could write a book about my time in Istanbul, even though I was only there one season.”

Carvalhal entered the madness of Turkish football at its most insane. A match-fixing crisis had erupted and Besiktas boss Tayfur Havutcu was thrown in prison.

It got crazier, since Havutcu was allowed to carry on running the club from his cell and Carvalhal was told he would hand back first team duties at the end of the season.

“When I arrived there nobody knew me, even though I’d been at Sporting Lisbon. They thought, ‘who is this guy?’

“I tried to bring my own assistants, but it was not possible. I was there alone, except for the assistants to the manager who was in jail.

“I started doing my job and we won some games and then did fantastically in the Europa League.

“We won the group stage, the first time a Turkish team had done that. That was the moment when the fans started to scream my name.

“Everywhere I went, they would give me flowers. There was one night game where a guy stopped his car in front of the team bus, then threw the keys away, just so that hundreds of fans could bang on the windows and cheer.”

The Europa League run included a 5-1 victory over Maccabi Tel Aviv, after which it was suggested to Carvalhal that Mossad, the Israeli secret service, may have been displeased by the outcome.

“That was a bit scary,” says the manager who went on to take over at Sheffield Wednesday. “But I loved my time in Turkey. It taught me so much.

“Not being paid our salaries was a problem, but it was a massive club and so myself and the players stayed because we respected the fans.”

Carvalhal insists he never saw any evidence of corruption.

“No-one ever came to me with anything like that and I was never approached. There was a scandal and the authorities were dealing with it.”

His time looked to be up when Havutcu was released before the end of the campaign, but Besiktas stuck with their new man.

“I had a lot of credit from the good results, so they decided they could not sack me. The fans liked me and were singing my name and I was able to finish the season.

“But I will always live with that club in my heart. Like I am an Owl and a Swan, I’m a Kartal (Black Eagle) – forever.”