Paul Pogba has revealed the debilitating effect that contracting Covid-19 had on his fitness.
The Manchester United midfielder tested positive for coronavirus in August, forcing him out of the France squad and into quarantine.
Pogba's form clearly suffered in the early part of the season, culminating in United's dismal 6-1 home defeat by Tottenham in which he conceded a penalty.
The 27-year-old had started just one Premier League match since that Old Trafford debacle, but he was thrust back into the line-up at West Ham on Saturday and responded with a stunning goal and a fine all-round display in their 3-1 win.
Asked how Covid-19 had affected him, Pogba told MUTV: "It's strange, it's hard to explain because you wouldn't understand.
"Even in training, I would say to the fitness coach that I feel strange. It's not me. I get tired very fast and I'm out of breath really fast.
"The first game of the season, I couldn't run. I was trying. I spoke with the manager, 'I will start the game and let's see', but I was very out of breath and it took me a long time to get back to my fitness and to get back physically good.
"It's good to get back in the team, and to score this goal to help the team get back in the game, it's very important for the team. I'm very happy for that.
"It's such a difference. I'm finding my rhythm as well. I feel so much better, I felt I could go again, control the game, getting the ball. That's what I like, myself.
"That's what I think is good for the team. I'm a team player. As long as the team wins, that's the most important, you know? That's why I came here and that's why I want to be successful."
West Ham led at the London Stadium through Tomas Soucek but Pogba hauled United level with a spectacular first-time shot from 25 yards.
The ball seemed to have curled out of play when United goalkeeper Dean Henderson punted it upfield to Bruno Fernandes in the build-up.
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And Pogba added: "The kick from Dean was a bit... we didn't know if it was out or in but we just went for it. I just went for it, I saw Bruno had the ball and I was free.
"I hit one in the first half, it didn't go well, but the second time it went in and I'm really happy with this."
Mason Greenwood and Marcus Rashford were also on target as United made it five wins out of five on the road this season.
Jarrod Bowen, Pablo Fornals and Sebastien Haller all missed chances to add to West Ham's lead, and Bowen admitted: "It's a lesson for us.
"No one misses on purpose but it's just about learning to take our chances and putting the game to bed."