Middlesbrough were left to rely on an 86th-minute Cristhian Stuani winner after throwing away a two-goal advantage in their 3-2 FA Cup fifth-round victory over League One side Oxford United on Saturday.

Boro had looked set for a comfortable progression following first-half goals from Grant Leadbitter - a penalty - and Rudy Gestede, but that lead was gone in 60 seconds when Chris Maguire and Toni Martinez struck exactly a minute apart.

Oxford's second-half performance deserved a replay but substitute Stuani was on hand to turn in a Fabio cross with four minutes of normal time left on the clock.

The result sends Boro into the sixth round for the first time since their last season in the Premier League in 2008-09.

Maguire may have played a key role in Oxford's mini-revival, but it was he who brought down Stewart Downing to concede the penalty from which Leadbitter rifled home the opener.

Oxford had acquitted themselves well before going behind and appeared to have pulled level when Maguire's cross curled beyond Brad Guzan, but the goal was ruled out for a push in the box, and Gestede doubled Boro's advantage two minutes later.

A Fabio cross from the left was sent back across goal by Adama Traore and Gestede executed an acrobatic bicycle kick to net his first Boro goal.

Martinez - also guilty of a miss in the opening two minutes - poked wide from six yards on the hour, but he would soon atone for that profligacy in a frantic minute of football.

First, Maguire floated a delightful 64th-minute free-kick over the wall from a central position and beyond the reach of Guzan.

The celebrations had barely died down when Martinez pounced on a Guzan parry to drive home the rebound, with Boro having conceded possession cheaply in midfield.

But Boro would ultimately break Oxford hearts, with Fabio's cross from the left eventually finding its way to Stuani at the back post, leaving the Uruguay international with a straightforward finish.