Pep Guardiola said his injury-hit Manchester City cannot maintain a high level for 90 minutes after Brighton’s late fightback at the Amex Stadium sent them to a fourth consecutive defeat.

City were without key players, most damagingly missing four central defenders, and their performance dropped off alarmingly in the second half as Fabian Hurzeler’s side hit them with goals in the 78th and 83rd minutes to dent their title aspirations.

Substitutes Joao Pedro and Matt O’Riley scored the goals that stunned the Premier League champions, cancelling out Erling Haaland’s first-half strike and leaving Guardiola to reflect on suffering four losses in a row for the first time in his managerial career.

Matt O’Riley scores Brighton's winner
Matt O’Riley scores Brighton’s winner (Adam Davy/PA)

“Today we played really good in the first half but we couldn’t finish the game,” he said. “We were not consistent to maintain our game and our intensity and press and be aggressive for 90 minutes.

“The level we are playing is really good in certain moments but we are not able to continue for a long time.

“I’m pretty sure when the players come back (after the international break) and we make some individual qualities in the team, we’ll be back.”

City were eliminated from the Carabao Cup by Tottenham as well as losing 4-1 to Sporting Lisbon in the Champions League on Wednesday, but it is back-to-back league defeats that have been the most costly.

After their 32-game unbeaten league run was ended by Bournemouth a week ago, this was another case of City not having the players available to get over the line.

Manuel Akanji and Nathan Ake were fit enough only for the bench while Ruben Dias and John Stones were not in the squad, meaning 19-year-old Jahmai Simpson-Pusey was given a first league start in central defence.

The makeshift backline came under pressure in the second half from Brighton that proved intolerable, Pedro levelling after a penalty area scramble then summer signing O’Riley capped just his second Seagulls appearance with a dramatic winner.

“It can always happen one time in a lifetime, right?” said Guardiola of his unprecedented fourth straight defeat. “Always there’s a first time. We’ve lost two games in the Premier League and we have to change it, get back to winning. We’re in the position that we are in the table.

“When the players come back I don’t have any doubt that we will be back to our best.

“Normally people lose games, right? Always there’s a first time in life. This is my challenge, our challenge, and I like to face it. I will not step back at all. More than ever I want to do it. We will try again.”

Brighton boss Fabian Hurzeler reflected on a fairy tale moment for his goalscoring substitutes as they made comebacks from periods out injured.

“I’m happy for Joao and Matt that they came back after a long time with this impact, they worked hard in rehab, they didn’t have an easy time,” he said.

“In life you get what you deserve, what you work for. Matt is a player with a positive mindset during injury, after surgery he came to the training ground and showed his personality.”