Sheffield United boss Chris Wilder has described Newcastle counterpart Steve Bruce as an "ultimate winner".
The Blades will bid to extend their unbeaten Premier League run to eight games against Bruce's Magpies at Bramall Lane on Thursday night.
Wilder played under Bruce 21 years ago when the latter began his managerial career with the Blades and the pair have been mates since – but their friendship will be placed on hold.
"There's a result on the line on Thursday and Steve, to have his career, as a player and a manager, means he is the ultimate winner in terms of his career achievements," Wilder said.
"I know Steve and I know him well and even though I count him as a friend in football, on Thursday there's a big result to be had by both clubs."
Wilder said their friendship had also been put on hold during Bruce's spell in charge of Blades' city rivals Sheffield Wednesday, prior to him replacing Rafael Benitez at his hometown club in July.
"I've always liked him," Wilder said. "It just got put on pause, on hold for a little while, but then it was on play again.
"He's an experienced manager and to work in the Premier League for the length of time that he has is testament to what he's about from a tactical and man-management point of view.
"You don't get given jobs in the Premier League if you're bang average.
"Steve's not bang average as a manager or as a person, so yes, I speak to him quite regularly and I'm certainly not surprised by the job he's doing at Newcastle.
"It's a big, big job. They're a huge football club and one that needs a big personality and they've certainly got that in Steve."
Bruce was not a popular replacement for Benitez, but after a poor start, and in the face of some fierce criticism from Newcastle fans, one defeat in five league games suggests he has steadied the ship.
The Blades sit six places and three points better off than Newcastle in the table, having not lost since a narrow home defeat to Liverpool in September.
"It's still all about the next point and the next three points," Wilder added. "That's it. An accumulation of points and a review at the end of the season.
"It has to be that way. We've not looked at any groups of games. We can't do, with the quality you're up against."