Rafa Benitez has posted a pointed message on a social media site ahead of Newcastle United's visit to the Etihad Stadium.
Benitez and captain Jamaal Lascelles had a disagreement over tactics ahead of last weekend's home game against Chelsea.
And Lascelles also had a heated exchange with team-mate Matt Ritchie.
Ritchie and Lascelles missed Wednesday night's Carabao Cup defeat to Nottingham Forest because of injury, but they could return against Manchester City tomorrow evening.
United manager Benitez brushed off the rows after the 3-1 loss at the City Ground.
“There are no big issues," said Benitez. "In the game, you want players competing and who care. There are things that can happen in the dressing room that can happen, but the atmosphere is good."
Benitez has posted a video clip on Instagram of himself with Lascelles and Ritchie in the gym at the club's training ground.
The caption reads: "Newcastle United FC training session. The hard work becomes easier when we have team spirit."