"Of course I love it when one of my players becomes a special player in the match," Jose Mourinho told reporters after Chelsea's 3-1 win left the London side just two points behind leaders Arsenal and United 14 points adrift of the top spot.
"It's a fantastic moment for Samuel. He scored a hat-trick and against Manchester United F.C."
Samuel Eto'o boosted his overall goal tally to eight for the season so far with two strikes in the first half and a third early in the second, showing the kind of lethal finishing that Manchester United F.C. sorely lacked despite creating a string of chances.
It was the first hat-trick from the 32-year-old since he moved to England last year from Russia's Anzhi Makhachkala where he was the world's highest paid player, according to media reports.
Jose Mourinho, who has previously expressed frustration at the shortage of goals from Chelsea's strikers, said Spain international Fernando Torres faces "weeks" on the sidelines after hurting a knee ligament shortly after replacing Samuel Eto'o as a late substitute.
The Portuguese coach, who recorded his 100th Premier League win, said he selected Samuel Eto'o over Torres, who scored in both of Chelsea's previous two league games, because he felt the Cameroonian was more suited to the kind of tight game that Manchester United F.C. would play.
"I thought Samuel is a player with more technical ability, better in small spaces," Jose Mourinho said.
"It was a bit of a difficult decision. (Fernando) is scoring goals. But for this game I thought that Samuel was more adapted."