Manchester City have won the treble.

Pep Guardiola's side beat Inter Milan in the Champions League final to win their third trophy of the season after sealing the Premier League and FA Cup.

City have done what their city rivals, Manchester United, achieved in 1999.

Incredible.

United fans certainly wouldn't have enjoyed seeing City beat Inter 1-0 thanks to Rodri's strike.

Even though City have surpassed United over the last decade, fans of the Red Devils always had the 'treble' card to play during arguments.

But now, City have matched that amazing feat.

It seems United players aren't too impressed either.

Brandon Williams' five-word message after Man City win treble

That's because Man Utd's Brandon Williams reacted immediately after City were crowned champions of Europe for the first ever time.

He took to Instagram stories to write: "Nobody wants a sloppy seconds," referring to the fact United achieved the treble first.

Cheeky.

To be fair, only one side can achieve the feat first and that was Man United.

Guardiola on Man City's 1999 treble team

Before the final, Guardiola was asked about the previous club that had pulled off the treble.

And he admitted that the 1999 United side were an incredible side.

“In my opinion what I remember, because I was a little boy, was how good they were,” he said. ”This is my first feeling. Ryan Giggs, David Beckham, Roy Keane, three or four strikers, [Andy] Cole, [Dwight] Yorke, [Teddy] Sheringham, Ole [Gunnar Solskjær]. I remember how good they were, otherwise you can not achieve it.

“Apart from the quality that they had, you have to be a special mentality, special characters of the team, the manager, the history of Old Trafford. These kinds of things always help to do these kinds of things. I don’t know how many years English football is in this world, but for only one team to do it, that means how difficult it is to do it.”