Diego Costa has revealed that linking up with then-manager Jose Mourinho was the main reason behind his move to Chelsea in 2014.
The 28-year-old joined the Blues from Atletico Madrid for a fee of around £32m, scoring 20 Premier League goals in his first campaign at Stamford Bridge to help his side to the title.
A more difficult second season followed, as results took a turn for the worse and Mourinho was shoved towards the exit by disgruntled players - Costa alleged to be among them - to signal the end of his second spell in West London.
Ahead of Sunday's league meeting with Mourinho's Manchester United side at Old Trafford, Costa insists that he has nothing but respect for the man who brought him to English football.
"In all honesty I always tell people that I am grateful to Mourinho because he helped me a lot," he told Sky Sports News. "As a player when you want to improve you always look for the best coach and Mourinho is one of the best.
"I wanted to come to Chelsea because of Mourinho. When I considered Chelsea I thought about the fact that Mourinho was here. He is a coach that demands a lot from his players, he wants the maximum.
"He helped me a lot and then what happened is that the following season didn't go well, these things that happen, but the truth is that Mourinho helped me a lot to improve as a player."
Costa has found the net 17 times in the Premier League this season, putting him behind Alexis Sanchez, Harry Kane and Romelu Lukaku in the division's top scorers chart.