Middlesbrough striker Dong-Gook Lee scored a rare goal to help his side secure their place in the FA Cup fifth round with a hard-fought victory over struggling Mansfield.

The Barclays Premier League side, 78 places above their League Two opponents, took a 17th-minute lead after the South Korea international scored his second goal for the club.

However, Billy Dearden's side responded in determined fashion and had it not been for two fine saves from goalkeeper Mark Schwarzer to deny striker Michael Boulding the result might have been different.

Their hopes were finally ended by defender Jake Buxton's late own goal but the home fans among a crowd of 6,258 headed home happy with their relegation-haunted sides efforts.

Middlesbrough dominated in the early stages as Julio Arca exuded class in midfield and the pace of Jeremie Aliadiere and Adam Johnson caused real problems for the Stags.

THE ingredients for a cup upset were all present - but Middlesbrough's professionalism ensured there would be no giant-killing at Field Mill.

Faced with determined opponents from the lower reaches of League Two, Gareth Southgate's side rolled up their sleeves and laid their bodies on the line to book a place in round five.

Robert Huth and David Wheater were particularly impressive at the back, and the duo's relationship is a key reason why Jonathan Woodgate has been allowed to leave the Riverside.

Mansfield gave it everything they had - particularly after the break - but the Teessiders withstood everything that was thrown at them.

They weren't as impressive going forward - Afonso Alves cannot arrive soon enough despite Mido's return from injury - but Dong-Gook Lee's opener always looked decisive. Not, however, that it excused a dreadful headed miss from the South Korean shortly before the interval.

A late own goal put some gloss on the result, and Boro can now look forward to Monday's fifth-round draw with relish. The North-East's cup specialists roll on.

They took the lead in the 17th minute when goalkeeper Carl Muggleton and defender Lee Bell got themselves into a tangle as they attempted to deal with Johnson's inswinging corner.

Defender David Wheater, who had scored in three of his previous five matches, passed up the chance of a fourth with a mis-hit shot but the ball broke to Lee, who gratefully accepted the chance to double his tally after a frustrating year on Teesside.

Boulding posed the Stags main threat and Schwarzer tipped his 35th-minute piledriver on to the crossbar and then clawed away his header from the resulting corner.

The Teessiders returned after the break knowing a second goal would effectively kill off their hosts, and they threatened twice within the opening three minutes.

But Wheater was unable to make the most of a Luke Young cross and Martin did well to block a shot from Lee.

Mansfield came close and almost equalised in the 52nd minute when Matt Hamshaw forced his way into the box to cross to the near post, but Boulding could only fire wide.

The home side were making a real push and were mightily aggrieved at referee Steve Tanner's decision not to award a penalty for a challenge on Stephen Dawson two minutes later.

Having seen Boulding fire over under pressure from Huth after 65 minutes, Southgate attempted to inject fresh impetus into his side by replacing the tiring Johnson with England winger Stewart Downing.

Mido joined the fray as a 71st-minute replacement for Lee but it was Arca who sliced Mansfield open seconds later after he robbed Bell and charged towards goal, only to leave Aliadiere with too much to do with a wayward pass.

As they searched for an equaliser the Stags found themselves exposed at the back, and last man Simon Brown escaped with a yellow card for an 84th-minute rugby tackle on Aliadiere.

Boro's nerves were finally dissipated three minutes from time when Buxton headed a Boateng cross into his own net to end his sides hopes of a late fightback.