Pep Guardiola has told Aymeric Laporte what he needs to do to break up the partnership between John Stones and Ruben Dias.
Laporte was sorely missed last season as Manchester City's title defence crumbled while he was out with a long-term injury, but the Frenchman has barely been used in recent months.
Some of that is down to illness and injury, but the performance levels of Stones and Dias are another big factor in explaining why Laporte has not started a league game since the defeat to Tottenham in early November.
Having started training with the team again this week following a hamstring problem, Guardiola hopes to welcome the player back into the lineup for Saturday's FA Cup game against League Two side Cheltenham Town.
Winning his place back in the XI on a more regular basis will be a challenge given Stones and Dias have conceded just one goal in ten games together.
However, the manager still believes that Laporte in top form is the best left-sided central defender in the world and challenged the 26-year-old to find that rhythm again.
"It depends on him. The quality is there so if he is in top form and his mind is open he is the best central left defender," he said.
"He has special qualities on the ball, he just has to be focused to come back in the best condition possible and he will have his minutes. After that, being in the team or not depends on the performance of everyone.
"We need him, as we need Nathan [Ake], we need Eric [Garcia]."