Pep Guardiola believes winning the domestic treble is more challenging than winning the Champions League.
City became the first ever team to win the English domestic treble after their 6-0 demolition of Watford in the FA Cup final on Saturday o add to their Premier League success and Carabao Cup win.
"I wouldn't say the best, but one of the best for sure. To be 10 months, play in all competitions, and to be the first [to win the treble], it means we have been consistent every few days during 10 months," the Spaniard told Sky Sports said when asked if this was his best season as a manager.
"I love the Champions League, but to do that is more difficult than to win the Champions League." he added.
Their 6-0 thumping of Watford was the biggest-ever winning margin in an FA Cup final at Wembley in more than a century.