Pep Guardiola chose to start Kelechi Iheanacho in Saturday's Manchester derby to show his players that he wanted to win the game.
The Nigeria international started for Manchester City at Old Trafford in the absence of the suspended Sergio Aguero and rewarded Guardiola with a goal and an assist in the 2-1 win.
The Catalan coach says he could have picked someone else to lead the attack, but the 19-year-old's presence sent a message to the rest of his team.
"He was the only striker we had in that moment," he told Manchester Evening News.
"I thought about many other options - but I thought in the beginning to show to my players that I came to win the game."
Kevin De Bruyne opened the scoring before Iheanacho doubled the lead, only for Zlatan Ibrahimovic to net before the break.
Guardiola was satisfied with his side's display against Jose Mourinho's United, as City made it four wins from as many Premier League games.
"I've conceded many goals against Mourinho's teams on the counter-attack because his teams are really good in that part of the game," he said.
"But in the first half we controlled it, we conceded maybe one or two counter-attacks, no more.
"It's really good. We defended the set-pieces well because they are stronger and taller than us and we defended really good."