Manchester City manager Pep Guardiola said Joao Cancelo's controversial goal in Tuesday's 5-0 win at West Bromwich Albion showed the importance of playing to the whistle.
Cancelo's 20th-minute strike came as several West Brom players stopped in anticipation of the referee blowing for offside after the assistant's flag was raised in the build up.
But after checking with the Video Assistant Referee (VAR) the referee allowed the goal to stand.
"I understand the complaints from the West Brom players and the manager," Guardiola told reporters. "But with this rule you have to follow the action until the end. Don't stop because with VAR it can be disallowed.
"It is a good lesson for us. Today it happened to West Brom, but it could happen to us."
Ilkay Gundogan scored twice, and Riyad Mahrez and Raheem Sterling also got on the scoresheet to seal City's seventh straight Premier League win.
City have moved top of the table on 41 points, one ahead of Manchester United, who play bottom club Sheffield United later on Wednesday.
City host Sheffield United on Saturday.
