Bruno Fernandes credited Cristiano Ronaldo's hunger after his fellow Portugal international scored his 700th club goal in Manchester United's 2-1 win at Everton on Sunday.
Ronaldo was introduced as a first-half substitute for Anthony Martial, who suffered a back injury, and brought up the landmark by firing under Jordan Pickford after racing onto Casemiro's pass.
Alex Iwobi's long-range strike had initially handed Everton an early lead, but Antony became the first player to score in his first three Premier League games for United to level the scores.
Ronaldo's 700th goal in club football arrived 20 years and two days after his first (for Sporting CP against Moreirense on October 7 2002), and saw him get off the mark for the Premier League season.
The five-time Ballon d'Or winner had endured a frustrating campaign prior to his outing at Goodison Park, only starting one league match under Erik ten Hag, and Fernandes was delighted to see him find the net.
"It is tough still counting goals for Cristiano because every week it seems like a new record," Fernandes told BT Sport.
"We're really happy because he has been working hard to get this goal, we saw it last Thursday, it was tough for him. Today he got the goal and the win.
"That's most important for Cristiano, I think, that the team wins, and obviously as a striker he wants to score goals and we are really happy for that."
United's comeback makes them the first team to win 100 Premier League games after conceding first, and Ten Hag was impressed by the Red Devils' response to Iwobi's fifth-minute strike.
"We were quickly 1-0 down but the reaction of the team was good," Ten Hag told BT Sport. "One of our aims is to deal better with setbacks and they stayed composed. It was quite impressive from our side.
"In the first half we were pressing well. Everton did not come out and it was difficult for them to get a lot of crosses in, we didn't allow them and I am happy with that.
"Casemiro will anticipate quickly, and we saw during the game how important he is, winning a lot of balls. He also played the ball for the goal from Cristiano Ronaldo. He grew into the game.
"Once again, we were happy with all the subs, Ronaldo coming on and getting the winning goal, and Rapha [Varane] showed his importance with his organisation and heading capacity."
United's victory moved them into fifth in the Premier League table, while their total of 38 wins against Everton in the competition is now their joint-most against any opponent (also Tottenham).