Ole Gunnar Solskjaer rotated his squad for Manchester United's recent Premier League clash against Everton, omitting Cristiano Ronaldo as one of five changes to the side that beat Villarreal in the Champions League.
Ronaldo scored a stoppage-time winner that night, but it was not enough to prevent the Portuguese superstar from being dropped to the bench - a decision which Sir Alex Ferguson believes was a mistake.
You can see the conversation with former UFC lightweight champion Khabib Nurmagomedov filmed in the aftermath of United's frustrating 1-1 draw with the Toffees on Saturday below.
Sir Alex Ferguson suggests that Ole Gunnar Solskjaer should have started Cristiano Ronaldo against Everton
"You should always start with your best players." [@MirrorFootball] #MUFC pic.twitter.com/7dLgZAu6s4
- MUFC Scoop (@MUFCScoop) October 4, 2021
Khabib appeared to stick up for United's younger players on the day, but Ferguson refuted these claims to a degree and highlighted the lift it would have given the Everton squad to see CR7 left out of the starting line-up.
Khabib: "These young guys versus a good team, they try to show their best performance."
Ferguson responded: "Of course. But I also think that when they saw Ronaldo wasn't playing."
Khabib: "Yeah, but he came on in the second half.
Ferguson: "I know, but you should always start with your best player."
Khabib on meeting Sir Alex: "He asked me if I wanted a glass of wine. I'm thinking, how I explain to him I'm a Muslim?
"So I said, drinking is not good for me because if I do then I will smash all of you guys up.
"He replied, 'OK, best if you don't drink'." #MUFC #bbcmma pic.twitter.com/rLxcuqUHHn
- Shamoon Hafez (@ShamoonHafez) October 3, 2021
Khabib and Ferguson were pictured alongside former Man United defender, Patrice Evra and legendary sprinter, Usain Bolt at Old Trafford on Saturday.
The retired Russian mixed martial artist clearly enjoyed shooting the breeze with Ferguson, who asked him about his health, while the Scot talked about Khabib's decision to retire from the UFC.
"Too much, too much. Now I'm tired of smashing people, no more I just like to enjoy," was Khabib's response.
He also appeared to rule out a comeback in the sport and another fight against Connor McGregor in the same conversation and called the Irish fighter an "invalid opponent."
Welcome to Old Trafford, Khabib :red_circle::seven:#MUFC ' #MUNEVE pic.twitter.com/DqkIKNafRu
- Manchester United (@ManUtd) October 2, 2021
Ronaldo has made an immediate impact upon his return to English football by scoring five goals in his seven appearances back at United, but their form is stuttering following a run of just one victory in four games after this latest setback against the Merseyside club.
The pressure is starting to mount for Solskjaer, who will be desperate to end the club's trophy drought that has now lasted four years since winning the UEFA Europa League in 2017.
Words by James Hilsum.