Luke Ayling's header deep into added time helped Middlesbrough secure a 1-1 draw against Leicester after Jordan Ayew's controversial first-half penalty at the King Power Stadium.
The final whistle was joyously celebrated by the away end but Leicester were booed off for a second successive home game.
Middlesbrough bossed the opening exchanges in terms of possession but the first chance was Leicester's, a back-post header by Abdul Fatawu that went wide.
Caleb Okoli spurned a great chance to put City ahead in the 19th minute when he stole in behind the Boro defence from Luke Thomas' free-kick but failed to make any contact in front of goal.
The visitors replied with a shot from Matt Targett that home goalkeeper Jakub Stolarczyk, who had required treatment earlier on, struggled to save.
Another Thomas free-kick almost undid the visitors but Julian Carranza could not hit the target on the turn.
Fortune favoured Leicester in first-half stoppage time, however, when referee Adam Herczeg made his controversial penalty call.
Fatawu charged down an attempted clearance by Aidan Morris, with the ball bouncing to Hayden Hackney right on the edge of the area.
The midfielder stuck out an arm and contact was certainly made but Boro insisted that had taken place outside the box. Ayew made no mistake from the spot to give City the lead.
Stolarczyk did not return for the second half, with Asmir Begovic replacing him for his first Leicester appearance since joining in the summer.
Morgan Whittaker curled on to the top of the net as Middlesbrough pressed for an equaliser, with Hackney also off target soon after.
Fatawu, already cautioned in the first half, escaped a second yellow for challenge that hurt Targett.
Middlesbrough felt they should have been awarded a penalty in the 73rd minute when Okoli barged Tommy Conway over but this time Herczeg was not interested.
Targett, Conway and Whittaker all missed the target as Middlesbrough searched for an equaliser in the closing stages.
Conway could not convert a great opportunity to level in the 87th minute when Jannik Vestergaard's error let him in, with Begovic making an important block.
Boro's Alfie Jones was shown a straight red in the 89th minute for cynically stopping substitute Stephy Mavididi from being sent clear.
But Ayling headed home in the sixth minute of stoppage time to spark wild celebrations in the away end.
Callum Brittain launched a cross to the far post and the centre-back beat Okoli in the air to head across goal.
The managers
Leicester's Marti Cifuentes:
To follow...
Middlesbrough's Rob Edwards:
To follow...