Craig Gordon believes John Mensah has played a leading role in Sunderland's return to form.
The Black Cats have taken four points from their last two outings to all but end any fears they had of being dragged into a basement battle.
Sunday's 1-1 draw with top-four chasing Manchester City proved they are capable of competing with the best sides in the division, with only a late Adam Johnson effort denying them a memorable win.
At the heart of the reversal in fortune has been Ghanaian centre-half Mensah, who has finally shaken off the niggling knocks which have hindered his progress since arriving in England from Lyon last summer.
The £8million man is starting to live up to his hefty price tag and Scottish shot-stopper Gordon is just one of many to have been impressed by the African ace over recent weeks.
"John's been unlucky with his injuries, but I think we're seeing the best of him now," he told the Sunderland Echo.
"He's put together a run of games and does not need to do a great deal in training because he's a naturally very fit lad.
"He must be very fit to just come out and play games - he's our Ledley King.
"The management have been very careful with the work he does between games and it's paying off because he's been a great influence."
Gordon has also hailed the benefits of playing in a settled team, with Steve Bruce having named Alan Hutton, Mensah, Michael Turner and Anton Ferdinand as his back four for three games in a row.
"I don't think it is any secret that if you get the same back four and goalkeeper playing together week in, week out, you get a much better understanding together," Gordon said.
"City had us under pressure for pretty much all of the second half and I had to make a few saves, but that's what I'm there for.
"We've not been allowing too many chances against us of late and I think that's down to the back four knowing each other better from playing alongside each other."