Maurizio Sarri broke new ground in the English top flight after Chelsea had a 0-0 draw against Everton.
Sarri has hit the ground running at Chelsea in his very first campaign in charge after leaving Napoli in the summer to replace Antonio Conte as head coach, and after seeing his side draw 0-0 with Everton at Stamford Bridge he overtook Clark to go 13 games unbeaten.
The Italian is the only manager in Europe’s top five leagues still to lose a competitive game as the Italian is now 18 games unbeaten in all competitions.
Speaking after the game against Everton, Sarri spoke about the run of wins and draws when asked if he was proud of the record.
“Yes I am,” he said to BBC Sport. “But of course I have to say thank you to the club because they gave me a very strong squad.
“I am happy with the second half. We played very well. I am not happy really with the first 25 minutes. We moved the ball slowly. But then I thought we played very well, especially in the second half.”
Sarri can claim to be the only manager still to be defeated across the continent’s top five leagues – the German Bundesliga, La Liga, Ligue 1, the Premier League and Serie A.