Jose Mourinho believes that having to prepare teams to take on Lionel Messi made him a better coach.
The Argentinian was a regular opponent for Mourinho in Spain when he was Real Madrid boss, and he also faced the Barcelona No.10 during spells elsewhere too.
“I always say that I owe so much to my players, and to those who haven't been my players but those who created problems for me,” the Portuguese said to EFE.
“For example, Messi never played for my team, but he played against me and he has made me a better coach for having to prepare matches [to stop him].
“When I say Messi, I also mean the other great players I've faced.
“Atletico Madrid have started this LaLiga Santander excellently and Mourinho thinks they need to be considered as heavyweights.
“I don't think Atletico are an emerging team anymore,” he explained.
“They've won the league in the last decade, they've won cups, Europa Leagues and have been in Champions League finals.
“Atletico are a candidate for the title. They lost [Antoine] Griezmann, [Diego] Godin but they've invested very well.
“His time at Madrid ended badly, but the door isn't closed on a return to the Spanish capital and he remembers his time there fondly.
“I had three good years there,” he said, “obviously with difficulties and problems, but that's professional life.
“It's not easy. I have fantastic memories. The time I had there was tough for Madrid, it was a period wherein Barcelona were dominant.
“We had to break that.”
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This article was most recently revised and updated 3 years ago