Bayern Munich winger Douglas Costa believes Pep Guardiola's success is down to an addiction to football.
On December 20, it was announced the Spaniard would be leaving the Allianz Arena when his contract expires at the end of the season, with Carlo Ancelotti taking his place at the helm.
The Bavarian giants are on course for a third straight Bundesliga title under Guardiola after taking an eight-point advantage into the mid-season break.
Costa says the former Barcelona coach is unlike anyone else he has worked under and changed his view on what the job is about.
"When I arrived at Bayern he asked me: 'How are you? Are you ready to learn how to play football?'," the Brazilian told Globo Esporte.
"Before, I thought the coach's job was just to set up the team. However, with Guardiola it's something different.
"He is addicted to football and because of that he is a phenomenon."
The 25-year-old has supplied seven assists since making the switch from Shakhtar Donetsk to Bayern ahead of the 2014-15 season and he feels working with Guardiola has improved his game.
"At Shakhtar I got back to defend more. Now I help Bayern score a lot, but I attack more," he continued.
"Guardiola can get the best out of everyone and that's why he is what he is."