EVERGREEN Aiden McGeady further justified Lee Johnson's decision to bring him back from the cold with the goal that prevented Peterborough going four points clear in second.

The 35-year-old Republic of Ireland playmaker, unloved and unused for so long by previous manager Phil Parkinson, conjured up a free-kick equaliser after Siriki Dembele had put Posh in sight of a seismic win. Top quality, top corner.

The Black Cats still have a game in hand over their hosts, who will regret not doubling their lead straight after breaking the deadlock in the only spell where Sunderland were second best.

Johnson handed Ross Stewart a first Sunderland start as one of three changes to the side that beat Oxford 3-1 on Friday, and the big Scot made his first contribution in the tenth minute with a knock-down for Charlie Wyke to unleash a shot from 22 yards. It took a deflection and landed just wide of Chisty Pym's left-hand post.

Posh were bristling with aggression and Louis Reed was booked in the 17th minute for a cynical body-check on Jordan Jones, who that saw Black Cats surround referee Craig Hicks demanding retribution.

Jones recovered to fire off a shot that pinged off Stewart's unsuspecting back as Sunderland continued to dominate.

Reed forced Lee Burge into his first save just before the half-hour mark with a long-ranger that bobbled a bit on Posh's infamous pitch but the keeper was able to gather without alarm.

That perked Peterborough up though and Burge had to rush out to stop Jack Taylor from sending Ward clear. Straight after Taylor set up Sammie Szmodics in the box for an effort Luke O'Nien blocked.

Jones was back in the wars a few minutes later; this time it was Dan Butler who was booked for sending the winger crashing to the turf.

Jonson Clarke-Harris, League One's top scorer, had hardly had a touch and none in a dangerous position but Harrison Burrows' cross from the left almost undid the Black Cats in the 41st minute. O'Nien had to go for it and ended up diverting it towards his own goal; Burge did well to react and gather.

The second half began with Szmodics miscueing a volley over and Wyke stinging Pym's palms from an angle at the other end. McGeady curled a free-kick just wide after Stewart had been hacked down on the edge of the box before Posh made a double change before the hour mark.

Posh went close to opening the scoring when Joe Ward skipped past Callum McFadzean to put Szmodics in space in the box but his shot flashed across goal.

Peterborough's next attack, in the 66th minute, ended with the ball in the back of the net. Sunderland complained that Ward blocked McFadzean off before Nathan Thompson slipped Dembele in for a silky finish but the goal stood.

Johnson responded with a quadruple substitution as Lynden Gooch, Conor McLaughlin, Aiden O'Brien and Denver Hume came on.

Burge had to bat away another Szmodics effort on the right of the box; it had taken a while but Darren Ferguson's side looked like the one going up automatically, the Black Cats the challengers.

McGeady changed that picture instantly in the 81st minute with a free-kick of perfection after Josh Scowen, seconds after replacing Winchester, was fouled by Taylor 22 yards out. That was ideal range for the ex-Celtic man, who cleared the wall and Pym with ease.

Posh breathed a sigh of relief with a minute to go when Max Power's cross hit defender Mark Beevers and bounced off a post.