ISTANBUL -- It was mission accomplished for Pep Guardiola on Saturday night at the Ataturk Olympic Stadium, and he did it with the big boss watching from the stands. By delivering Manchester City's first Champions League title, Guardiola has done precisely what he was hired to do by owner Sheikh Mansour bin Zayed al Nahyan, but by achieving a treble at the same time, he has added the most incredible flourish.

Simply put: Manchester United are no longer the only English club to win the Premier League, FA Cup and Champions League in the same season. Their 1999 triumph has now been matched by Guardiola's City after Rodri's 68th minute goal sealed a 1-0 win against Inter Milan.

Since arriving at the Etihad in 2016, Guardiola has won five Premier Leagues, masterminded a domestic treble in 2019 and guided City to 100 points -- the only team to do so in the Premier League era -- in the 2017-18 season. Despite all that success, the Champions League had been a tale of failure and near-misses, including losing the 2021 final against Chelsea in Porto.

Guardiola had even said before this game that his City side -- and his time at the club -- could not be regarded as legendary until they won the Champions League. But the wait is finally over, and Istanbul will always now mean just one thing to City and their supporters: ultimate glory.

"It was written in the stars," Guardiola said. "It belongs to us. I'm tired. Calm. Satisfied. It's so difficult to win it."

This was certainly City's night, but it is really Guardiola's achievement and his tearful relief at the final whistle told the story of the pressure he has been under to make the club European champions. Sheikh Mansour's presence at the game probably added to that stress. Despite pumping over £2 billion into the club since buying City in September 2008, he had only previously been to one game, a home win against Liverpool in 2010. The prospect of having to say "sorry, better luck next time" to the man who has bankrolled Guardiola's team-building project was one the former Barcelona and Bayern Munich coach probably didn't want to contemplate.

There's no doubt Guardiola has been indulged like a favourite child by Sheikh Mansour and the club's Abu Dhabi hierarchy, but he is the best manager in the world, and perhaps the best of all time -- he has been indulged for a reason. He has welcomed the players he's wanted like forward Erling Haaland, midfielders Rodri and Ilkay Gundogan, winger Jack Grealish, defender Ruben Dias and goalkeeper Ederson, who made two crucial saves from Romelu Lukaku and Robin Gosens as Inter chased a late equaliser, but he has made them all better.

So many clubs have spent fortunes on shiny new signings and failed to see their investment repaid with success. Just look at Chelsea over the past 12 months or United in the 10 years since Sir Alex Ferguson retired. Money doesn't guarantee success. It helps, of course, but no manager or coach in the game right now is able to demand -- or get -- so much from his players like Guardiola. Some, including John Stones, Kyle Walker and Manuel Akanji, have had their games elevated to a whole new level by the former Barca midfielder.

And yet the irony of their victory against Inter is that it was achieved without any of the flair or dominance that have come to mark Guardiola's City. In the end, Inter didn't meet the same fate as other elite teams like Liverpool, Arsenal and Real Madrid, all of whom were ruthlessly dismantled over the closing weeks of the season. The Serie A side were dogged and disciplined, with coach Simone Inzaghi's tactical plan clearly frustrating City.

Guardiola was pained on the touchline at times, especially when an Akanji mistake gifted a chance to Lautaro Martinez that was wasted by the Inter forward. (Ederson did well to narrow the angle and keep his body behind the ball, making the stop look easy.) The City manager also had his head in his hands when Lukaku and Gosens went close to equalising in the final minutes, which could have taken the game into extra time.

- Stream on ESPN+: LaLiga, Bundesliga, more (U.S.)

Even though Inter made City fight for the victory, Guardiola's side found a way. Phil Foden, a first-half substitute for the injured Kevin De Bruyne, was the spark who upped the tempo, which led to Rodri scoring the game's only goal after Inter failed to prevent Bernardo Silva's cross from reaching the defensive midfielder near the edge of the box.

However, City were still unconvincing after taking the lead. It was probably their worst performance for months -- Inter also hit the crossbar via Federico Dimarco -- but they held on to win.

"This is a really proud moment for everyone at this football club," City captain Gundogan said. "We work so hard every single day and we have wanted to win this trophy for so long. The Champions League is a beautiful competition and we are all incredibly happy to have won. This team deserves the highest recognition, and winning the Champions League elevates us to the very top of the game.

"To win the treble is something amazing. It is the ultimate achievement for any club team, and we have done it. It reflects the quality we have in our squad, but it also shows how dedicated we are."

It is a triumph that also means Guardiola can now look Sheikh Mansour in the eye and say he's done everything asked of him and more. His City side have consistently been the best in England, and now they are definitively the best in Europe. They have broken records galore and even taken United's proudest claim of being the only treble winner in England. United are now not even the only treble winner in their own city.

All of that is down to Guardiola. While he remains at the Etihad, anything is possible and City can now target other milestones. For example, no team has won four successive English titles, but City can do that next season. No English club has retained the European Cup since Liverpool in 1978, another mark City could match in 2023-24.

Guardiola has taken City to the sport's highest possible peak and they don't look like leaving it anytime soon.