James McFadden has lauded former Everton team-mate Duncan Ferguson as "the best professional I have ever come across".
McFadden moved to Goodison Park from Motherwell when fellow former Scotland striker Ferguson was in his second playing spell at the English club.
"He was an unbelievable professional - first in, last away, always in the gym," McFadden told BBC Scotland.
"Every day, he did extra shooting and working on his touch."
McFadden pointed out that, while Ferguson was renowned for his aerial prowess, all that practice also meant "he was great with the ball at his feet".
Ferguson built a reputation as an abrasive character on the field of play and for guarding his privacy off it, but McFadden found the 45-year-old to be a "really nice guy".
"When I first went to Everton, it took him a year before he spoke to me because he was probably sussing me out," he told Sportsound. "He doesn't let you in easily.
"I trained with him every day, but I don't know how many conversations I'd had with him.
"At the end of the season, in Marbella, I had a drink with him. He had a load of time for you as long as he got to know you."
Ferguson only won seven international caps, having refused selection after 1997, in part in protest at receiving a 12-game ban from the Scottish FA for an on-field assault on Raith Rovers' John McStay.
"He was hard and there were a couple of times he let himself down when he came on the park, but he was a great professional," said McFadden.
Ferguson remains on the Everton coaching staff and McFadden thinks his fellow Scot could be manager one day.
"He loves Everton obviously and that is where he will be if he's ever a manager," he said.
"If he doesn't become the manager, I think he'll coach there as long as he wants."
McFadden, who signed for Queen of the South last week after his summer release by Motherwell, also has fond memories of Davie Moyes from his time as Everton manager.
"Davie Moyes used to give me a hard time every day and I used to think, 'Why did he sign me? He's on my case all the time'," said the 34-year-old.
"It wasn't until I left I realised just how good he was. I knew he was a great manager, good coach, but I didn't realise he was helping me at that time because I thought I had to get him off my back.
"He worked on you every day. He was the one who demanded the best of you every single day. He probably got the biggest improvement out of me."
McFadden also worked under Alex McLeish when he was Scotland manager and was later signed by his compatriot for Birmingham City.
"The one I had the best relationship with was Alex McLeish," he said. "I could speak to Alex about anything."
McFadden also praised his managers at Motherwell, where he began his career.
"Starting out, Billy Davies was excellent, a great coach," he said. "He was hard on the younger ones, but every manager was back then.
"I thought Eric Black was excellent. He put me in the team and kept me there.
"I had never played up front before and we never had any strikers, so he said go and play up front.
"I think I scored five goals in the first four games and that was it. He made sure that he got the best out of me.
"Also, Terry Butcher. I have always got on well with them."