Manchester United manager Ole Gunnar Solskjaer and City counterpart Pep Guardiola brushed aside their differences in a wonderful moment of sportsmanship after the latest Manchester derby.
Solskjaer's United snapped City's 21-game winning streak in all competitions with an impressive 2-0 win on their fierce rivals' home turf at the Etihad.
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City's pursuit of a world-record winning streak ended after goals from Bruno Fernandes and a rare strike from Luke Shaw.
There weren't too many sparks on the pitch in a fairly well-mannered derby showdown, but tempers did flare up between the two managers on the touchlines in the second half.
An ankle injury for United forward Marcus Rashford proved the catalyst for the incident, with the visitors bringing on Mason Greenwood after goalkeeper Dean Henderson intentionally kicked the ball into touch so his side could make the substitution.
Rather than giving the ball back to United, the home side took a quick throw-in, leading to Solskjaer and Guardiola exchanging some heated words on the sideline.
However, in a touching aftermath to their angry confrontation, footage taken after the match showed both managers engaged in a friendly chat on the pitch, long after the final whistle had gone.
With the cameras no longer rolling, amateur footage showed Solskjaer and Guardiola chatting arm-in-arm as they walked along the side of the pitch.
Guardiola was also keen to move on from the second half argument when asked about it in his post-match interview.
“No problem it is solved," he told media.
City's incredible unbeaten run took just over 30 seconds to appear in trouble when Gabriel Jesus tripped Anthony Martial in the box, with Fernandes converting the penalty to give United a stunning start.
Fernandes's early penalty and Shaw's first Premier League goal for three years moved United back into second place, 11 points adrift of runaway league leaders City.
"Today we did almost everything perfect," Fernandes said.
"The league is not a sprint, this is a marathon. We have to do our best and not think about others."
United reclaim second spot
A third win in nine league games takes United back above Leicester and opens up an eight-point cushion in the battle to secure a top-four finish, with Solskjaer conceding that City have the title all but sewn up.
City had not even trailed in a Premier League match for 20 games stretching back to their last defeat to Tottenham in November.
"We played good apart from the first 10 minutes," said City boss Pep Guardiola.
"Unfortunately we could not be clinical up front.
"The news is not today, the news is 21 victories in a row. This result is going to help us a lot to understand how difficult it is. The important thins is the next one. There are 30 points to play for and we need to win again."
Guardiola's men began to take control as the first-half wore on, but Dean Henderson was only forced into a couple of routine saves by Ilkay Gundogan.
The hosts came much closer at the start of the second period when Rodrigo side-footed against the post after a patient build-up involved Riyad Mahrez and Jesus.
Seconds later, City were caught out by a brilliant United counter-attack as Shaw ran from inside his own half, exchanged passes with Marcus Rashford, and then fired into the far corner for the Red Devils' first goal from open play against a traditional top six opponent in eight league games this season.
Solskjaer's men beat City in both meetings at the Etihad last season by picking their neighbours off on the break and used the same tactic to great effect for another fine win.
Martial should have ensured a much greater margin of victory as he twice fired too close to Ederson with just the goalkeeper to beat.
City had the chances to at least avoid defeat in the closing stages as substitute Phil Foden sliced wide from point-blank range before Raheem Sterling completely missed a tantalising cross from Kyle Walker with the chance to score his first goal against United.
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