Phil Foden score his 15th goal of the season to put City ahead in the 25th minute when he tapped in Erling Haaland’s square pass after the striker had broken free.
But a wonderstrike from Julio Enciso pulled the Seagulls level before half-time to end City’s 12-game winning streak in the Premier League.
Haaland thought he had headed in a 79th minute winner but the Norwegian remains on 52 goals for the season after his effort was ruled out following a VAR check.
What happened
With several senior players left out of the trip to the South Coast, City lined up with Rico Lewis at left-back and Rodrigo dropping into the back four alongside John Stones.
Guardiola made six changes with Haaland recalled to the starting line-up and the City striker almost headed us ahead inside six minutes.
Foden crafted the opportunity with a clever jinking run before picking out Haaland at the backpost but his effort was just inches over the bar.
SHOP THE PREMIER LEAGUE CHAMPIONS RANGE
Brighton, who have secured European football for the first time in the Club’s history, offered plenty of threat and rattled the woodwork in the 20th minute.
Danny Welbeck hit a free-kick low into the hands of Stefan Ortega Moreno and when he got a similar opportunity shortly after, his effort smashed the top of the crossbar.
But City broke to the other end with Haaland racing clear, but a heavy touch saw Brighton keeper Jason Steele close him down.
Moments later he was put through again by Riyad Mahrez and this time he squared to Foden whose shot beat Jan Paul van Hecke stationed on the goal-line.
The Seagulls had the ball in the net on the half-hour when Kaoru Mitoma bundled a corner over the line, but referee Simon Hooper disallowed his effort for handball with the Japanese winger almost carrying the ball in his arms.
But the equaliser came seven minutes before the break when Enciso rifled an unstoppable 25-yard strike into the top corner.
City made a quick start to the second half with an Ilkay Gundogan effort deflected wide and substitute Cole Palmer hitting a stinging shot that Steele palmed away.
At the other end, Ortega Moreno made two smart saves to keep out strikes from Evan Ferguson and Mitoma as they found space in the box.
Haaland found the back of the net in the 79th minute when he headed in Palmer’s cross but the referee was sent to the VAR screen and disallowed the goal for a pull on Levi Colwill’s shirt.
But neither side could find a winner and Guardiola and Roberto De Zerbi embraced warmly at the full-time whistle.
That’s entertainment!
For a game that had little riding on it, there was no end-of-season feeling in a highly-entertaining penultimate game of the Premier League campaign.
Guardiola was full of praise for De Zerbi and his Brighton side ahead of the game after the Italian guided them into a European place.
A young side pushed throughout and City fans behind the goal showed their respect for Enciso’s wonderful equaliser, with some clapping the strike as the ball hit the back of the net.
And there was no signs of City taking a backward step despite the big finals on the horizon.
A front-three of Foden, Haaland and Riyad Mahrez caused the home side plenty of problems with De Bruyne as ever pulling the creative strings and we kept pushing for a winner with a Haaland effort ruled out late in the game.
Player of the match
It was another test for Lewis to step into and once again the 18-year-old excelled.
Brighton pressed high up the pitch putting Ortega Moreno and the back-four under pressure.
Lewis, playing at left-back, was happy to take the ball and calmly get past the Seagulls forwards.
And he was still prepared to push into midfield and beyond, picking the ball up on the edge of the box and testing Steele with one strike.
Pep Guardiola reaction
“We showed what we have done with and without the ball. I didn’t see one drop in our intensity and idea. They had chances, we had chances, we scored a goal, they scored a goal.
“Both teams want the ball, both teams want to press. The keepers are fundamental in this game. The quality they have, they are an exceptional team.”
RODRIGO REACTION
“It was a big, big test for us. We have to maintain the level.
“We are thankful to win the Premier League with three games to go but it is not easy to keep the level.
“You need to rest but at the same time you have to keep the energy.”
Teams
BRIGHTON: Steele, Van Hecke, Colwill, Caicedo, Estupinan, Gross, Gilmour (Mac Allister 51), Enciso (Ferguson 51), Buonanotte (Veltman 75), Mitoma, Welbeck (Undav 75).
Subs: McGill, Ayari, Webster, Dunk, Peupion.
CITY: Ortega Moreno, Walker, Stones (Gomez 84), Rodrigo, Lewis, Gundogan (C), De Bruyne (Alvarez 57), Bernardo (Phillips 84), Mahrez, Foden (Palmer 51), Haaland.
Subs: Ederson, Charles, O’Reilly, Robertson, Knight.
What it means
With the Premier League title already secured, the game was about more than collecting three points.
City extended their unbeaten run and Guardiola was also able to refresh his starting line-up and maintain the momentum going into the final weeks of the season with an FA Cup final against Manchester United and Champions League final with Inter still to come.
He made six changes to his starting line-up after making nine alterations at the weekend in the 1-0 win over Chelsea before we lifted the trophy.
What’s next
We have one more Premier League match to come, wrapping up the season away to Brentford at 16:30 (UK) on Sunday.
That’s followed by two more shots at silverware with United in the FA Cup final at Wembley on Saturday 3 June before Italian side Inter in the Champions League final in Istanbul a week later.
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