There is plenty of fight left in Manchester City but they spent too much of this game doing battle with themselves. While much attention is rightly paid to the moodiness of the greatly talented Mario Balotelli, there should be scrutiny to spare for others. It does no credit to the manager, Roberto Mancini, that the side's display was so dishevelled. Sunderland were far smoother and did not deserve to have a 3-1 lead annulled in the last five minutes.

City, losing that perfect record of Premier League victories at the Etihad, drooped just when they were expected to reach parity with the leaders, even if Manchester United do have their game in hand at Blackburn Rovers on Monday. Any accolades for the hosts lie in the fact that they refused to be deterred by their own ineptitude and the idiosyncrasies of Balotelli, who was as much of a menace to the good order of his own team as he was to Sunderland.

His astonishing squabble with Aleksandar Kolarov over who should take a second-half free-kick was the low point of another perplexing display and Mancini was frank in his disapproval, having stated before the game that he could not trust Balotelli. "Mario played like I said about him [on Friday]," the manager observed. "He can do nothing like he did today for 70 minutes but score two goals."

Martin O'Neill, the Sunderland manager, has a promising side if this display is any guide. The Benin midfielder Stéphane Sessègnon was a fount of creativity that Mancini, right, must have envied despite all the accomplishment contained in his own squad. Sunderland might well have taken the win had the centre-half Matthew Kilgallon, who has suffered with injuries, not gone off in the 83rd minute when that 3-1 advantage appeared impregnable.

Any tributes to City's recovery would not be entirely to the liking of Mancini. The side scrambled for a point on a field where they have been unassailable in the league. Any examination of this display will focus on the dullness of the players for almost all of the match, even if they did regain some appreciation for the determined recovery that secured a point.

City's mental state had not been so lucid at the start and Edin Dzeko recognised that failing. The forward did not reject suggestions that his team was initially complacent. "We had won all our home games [in the league]," he said, "so maybe we thought we could count on all three points – but it's not like that and you have to fight for every point."

With very little at stake Sunderland, after their defeat in the FA Cup replay with Everton, could scarcely have been more pugnacious. It was O'Neill's lineup that reeked of ambition. Considering that United play their final game of the season at the Stadium of Light on 13 May, it is possible that Sunderland will have a further say in the title's destiny.

O'Neill's side posed plenty of questions here, particularly once Sessègnon broke on the wing and picked out a reinvigorated Sebastian Larsson, who converted the chance with ease for the first of his goals. Balotelli did equalise with a penalty two minutes from half-time after Craig Gardner had made contact, however slight, with Dzeko, but Sunderland regained the lead in first-half stoppage time as a Sessègnon cross saw Nicklas Bendtner head powerfully past Joe Hart.

The situation seemed irretrievable when Sessègnon once more shaped the action in a move that then allowed Larsson to claim his second goal after 55 minutes. City were never to impress greatly but they had a perseverance crucial to any side vying for the title. Balotelli's talent also told when he cut in from the left to fire an impressive drive across the goalkeeper Simon Mignolet in the 85th minute. Another fine shot, from Kolarov, soon levelled the score.

There was ultimately a coherent and determined approach by City. Perhaps all sides who eventually take the title can recall afternoons when they muddled their way a little nearer to the prize but the club does have specific areas of concern. David Silva was removed here before the hour , yet he had been the brightest light for City and arguably the best player in the Premier League for much of the campaign.

The chase for honours has tired him in mind as much as body. City do not quite have the limitless alternatives popularly supposed to be at Mancini's disposal and he also had to explain that someone such as Samir Nasri could not be included because he was affected by tiredness and an unspecified "family problem".

The Frenchman might well be experiencing a commonplace situation but nothing is routine at a club aching to be champions of England for the first time since 1968.

Man of the match Stéphane Sessègnon (Sunderland)