Across two spells with Chelsea and one with United, Mourinho becomes the 13th coach to achieve the milestone of a triple-century and his record is very impressive indeed.
Mourinho has the most wins of any manager in their first 300 games, while his defensive record is similarly supreme. Everton are his favourite opponents.
We take a look at those statistics and more with the help of Opta, recapping the Portuguese’s 300 league matches in English football.
39 – Mourinho’s first 50 Premier League games yielded 39 wins for a points-per-game ratio of 2.52. That remains his most successful period as a Premier League manager.
189 – Mourinho has the most wins of any manager in their first 300 Premier League matches, racking up 189 victories.
183 – Of the other Premier League managers to have reached 300 Premier League games, Alex Ferguson’s 183 wins is the closest to Mourinho’s tally of 189.
34 – Despite conceding three goals at City on Sunday, Mourinho has the best defensive record of any manager in their first 300 games. His teams have conceded 230 goals – 34 fewer than Arsene Wenger, who had the next best record.
0 – Wolves are the only team Mourinho has faced as a Premier League manager and not beaten, drawing his sole meeting with them 1-1. He has a 100 per cent win record against Wigan Athletic, Cardiff City, Queens Park Rangers and Sheffield United.
10 – Everton have been beaten 10 times by Mourinho sides – more than any other club. Liverpool, West Ham and Crystal Palace are next with nine defeats.
49 – Frank Lampard has scored more Premier League goals for Mourinho than any other player, the England midfielder hitting the net 49 times under the Portuguese.
20 – Since Mourinho took charge of United at the start of the 2016-17 season, nobody has scored more times for him than Romelu Lukaku, who has 20 goals in that time. Anthony Martial moved onto 19 on Sunday.
17 – Paul Pogba’s 17 assists are the most of any United player during Mourinho’s time in charge at Old Trafford. Martial’s 11 make him the only other player in double figures.
15 – Former England captain John Terry scored 15 goals for Chelsea across Mourinho’s two spells at Stamford Bridge, more than any other defender