Lisandro Martinez said there was a "different energy" about Manchester United in their 2-0 win against Manchester City on Saturday – Michael Carrick's first game as interim manager.
The former United midfielder was on Tuesday appointed until the end of the season to replace the sacked Ruben Amorim.
Goals from Bryan Mbeumo and Patrick Dorgu secured a morale-boosting victory at Old Trafford against title-chasing City, who remain six points behind leaders Arsenal.
United climbed to fourth in the Premier League table ahead of the later kick-offs.
🛡️ Lisandro Martínez against Manchester City:
— The Touchline | 𝐓 (@TouchlineX) January 17, 2026
• 11 defensive contributions
• 8 clearances
• 2 recoveries
• 100% duels won pic.twitter.com/BIUG5zpIND
"Unbelievable, Unbelievable," Argentine defender Martinez told Sky Sports. "Being here with the fans, with the team we really know how we suffer during the season.
"But the only way is putting the face here and showing here who we are. Today is the best moment to do it. Not just the players on the pitch, the staff, everyone was part of that.
"I think one important thing that Michael Carrick said was 'Use the energy of the people' and today I think we did it and when we are together like this it is impossible to lose at home."
He added: "Today we defended so good, we were compact all the times. And then you have the confidence to go to the duels. Today you feel a different energy when you see the eyes of the players. Today the team won and that is the most important thing."
Carrick previously had an unbeaten three-game stint as caretaker boss at Old Trafford in 2021