Elsewhere on a busy night of action, 10-man Chelsea went down 2-1 at Fulham in front of new boss Liam Rosenior and Antoine Semenyo scored a fairytale winner for Bournemouth against Tottenham.
Erling Haaland scored his 150th City goal from the penalty spot to put Pep Guardiola’s team ahead at the Etihad but Kaoru Mitoma levelled in the second half.
Norway forward Haaland has reached 150 goals in all competitions in his 173rd appearance, 28 games faster than any other Premier League player.
Brighton scored a deserved equaliser in the 60th minute when Mitoma picked out the bottom corner from the edge of the area.
Haaland and his teammates squandered a succession of chances to draw their third game in a row.
City are now on 43 points, five behind Arsenal, who can go eight clear with a home win against Liverpool on Thursday.
Villa are also on 43 points following a goalless draw at Crystal Palace.
Chelsea’s new boss Rosenior watched his new charges from the stands at Craven Cottage.
The Englishman, who replaced the departed Enzo Maresca this week, will be in the dugout for the first time at second-tier Charlton in the FA Cup third round on Saturday.
The former Strasbourg boss said before kick-off that the team “need to hit the ground running for the rest of the season”.
But, still under the interim leadership of Calum McFarlane, they were reduced to 10 men midway through the first half when Marc Cucurella was shown a straight red card for hauling down Harry Wilson.
Liam Delap cancelled out Raul Jimenez’s opener but Wilson scored what proved to be the winner from the edge of the area.
Bournemouth beat troubled Tottenham 3-2, with Semenyo scoring from outside the area deep into stoppage time on his 26th birthday.
The winger, expected to join City over the next few days, was given a standing ovation when he was substituted moments before the final whistle.
Brentford beat Sunderland 3-0 courtesy of two goals from Igor Thiago, who now has 16 Premier League goals this season, and one from Yehor Yarmolyuk. The win lifts Brentford to fifth in the table.
Everton, reduced to nine men late in their match, held on to draw 1-1 with bottom club Wolves. (AFP)
