GIVEN that a clean sheet in this evening’s semi-final decider with Brentford will guarantee Middlesbrough a place in the play-off final at Wembley, Aitor Karanka’s side will take considerable comfort from finishing the regular Championship season with the best defensive record in the division.

In their 46 matches, Boro conceded just 25 goals. They were especially strong at the Riverside, letting in just 12 goals in their 23 home games, and the likes of Dimi Konstantopoulos, Daniel Ayala, Ben Gibson and George Friend all played crucial roles in constructing such an impressive set of defensive statistics.

Karanka’s training-ground work with his defenders was also crucial, but speak to any member of the Teessiders’ backline, and they will quickly highlight two more people who were absolutely integral to Boro’s defensive strength. Crucially, they will both be in their usual stations this evening, attempting to keep things tight once more.

Grant Leadbitter and Adam Clayton have formed a formidable defensive-midfield unit this season, and for all that Boro’s defenders have impressed, the fact that so many opposition attacks were snuffed out before they reached the last line of defence was a key factor in enabling the Teessiders to keep so many clean sheets.

Leadbitter has spent his entire career doing the dirty work at the heart of midfield, but when Clayton joined Boro from Huddersfield Town last summer, he did so with a reputation for being a creative playmaker with an eye for goal.

Nine months on, and while his goalscoring prowess is still to be witnessed, his energy, tackling ability and positional discipline have enabled him to emerge as one of the most important members of the Middlesbrough squad.

“I’ve done a totally different job this season to the one that I normally do,” said Clayton, whose appearance in the first leg was his 43rd start of the campaign. “Before I came here, I’d have said that I was an attacking midfielder, but now I’d definitely say I’m a defensive midfielder with the way I’ve been asked to play.

“I’ve had to change my game, but I think playing alongside Grant we definitely complement each other quite well. He’s a good player and it’s easy to play with good players. If you’ve got two players in there who are not bad at football, and they’re disciplined with it as well, then you’ve got half a chance.”

Clayton’s willingness to adapt his personal ambitions for the good of the team is commendable, but hardly unique amongst the current Middlesbrough squad. His midfield partner has claimed that this is the best team spirit he has known.

Leadbitter said: "“Us as players in the dressing room, we don’t want tomorrow night to be our last game together. We want another game to go so we have to perform.

"The team spirit in the dressing room is phenomenal. Team spirit comes when you are winning games and we have been winning games the majority of the year.

“It is the best dressing room I’ve been in in my career. The camaraderie between the English and foreign players, we all get on well. There is a winning mentality in the dressing room, nobody likes losing and that comes from the manager. Every day in training is intense and you don’t want to lose. It is about the players’ characters - they want to succeed and to succeed you have to have a good dressing room."

Last Friday was the first time Leadbitter had featured in a play-off match after previous spells at Sunderland and Ipswich Town. The Fencehouses-raised midfielder's only experience of the post-season games came as a 12-year-old, where he went to Wembley in 1998 to see the Black Cats play out a 4-4 draw with Charlton Athletic – but he admitted he didn't watch the decisive penalty shoot-out where Michael Gray missed a penalty.

“Yes, I remember that day," said Leadbitter. "I was there. I didn’t watch the penalties. I was outside on my own, I was just 12. I didn’t dare watch them.

"I had my head in my hands so I can’t remember too much. That is the past but it will be nice to have some happier memories in the play-offs.

"These are my first play-offs as a player. It is good fun - two-leg games, two good teams, and hopefully we will win."

Leadbitter would not be drawn on which side he'd rather face if Middlesbrough were to make the play-off final, but denied that talk of Wembley was banned around the training ground. He replied: "No, but we just think about the next game.

"That is one thing we have done all year, whatever team it is – whether it is Man City or Arsenal away in the cup, the biggest thing has always been the next game. That has come from the top to the bottom of the football club. That’s what the manager tells us.

“It is a big game, not just for myself but for the whole dressing room and we can sense that this week in training. There has been a sharpness and a bit of bite about us which is what you want going into a big game."