IN A quiet corner of Broadwood, a secret of Brendan Rodgers’ success is revealed. Stephen Dobbie has completed a training session with Queen of the South and is beginning to recall the 2011 Championship play-off final, when Swansea City won promotion to England’s top flight.

The forward scored at Wembley that day, with Dobbie absorbed quickly by the mass revelry of team-mates and bibbed substitutes overcome after watching the Welsh side establish a three-goal lead in the first half of the match with Reading.

Next to the mob stood Rodgers. He was peripheral amid such jubilation but was at the very heart of the spirit shown by a side which earned promotion at the end of his first season in charge. By the time they arrived in London, the Swansea players were willing to follow the Northern Irishman anywhere. He took them to the Premier League for the first time in the club’s history.

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Rodgers’ first year at Celtic could also culminate in a remarkable achievement as the Glasgow side close in on the treble, with only the Scottish Cup still to be won. Celtic will reach the final of that competition should they beat Rangers on Sunday.

The Scottish champions are expected to progress to the latter stages of domestic competitions, but Dobbie found the scale of their success this term easier to predict once Rodgers was appointed manager.

The forward excelled under the Northern Irishman as Swansea finished third in the Championship six years ago, scoring twice during the play-offs. He recognises immediately the work of a coach who has this season been meticulous in creating a side unbeaten in domestic competition, and whose diligence has resulted in Celtic mastering previously foreign concepts such as playing out from the back.

“What he does in training has a lot to do with why Brendan has been so successful. But it goes beyond that,” says Dobbie, who joined Swansea in 2009 following his first spell with Queens.

“He is so good with his players’ families – he would always go and speak to them, speak to the kids, and it was that which made the players at Swansea go up another level. It made us want to go and get better for him.

“You can see that is still how he works when you watch Celtic. Players like [Stuart] Armstrong have been transformed by Brendan this season. He is a very good man-manager. 

He always knows who he has to put an arm round and who he needs to shout at.”

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Rodgers might have been tempted to raise his voice following his side’s draw with Ross County last weekend; a match in which the Dingwall side scored with an unjust penalty, inciting Scott Brown to commit the lunging tackle for which he was sent off. The Celtic captain is free to play at Hampden on Sunday, but an encounter with Rangers has the capacity to ignite tempers made hot by events in the Highlands.

Rodgers was critical of the match officials last weekend at Ross County who gained a draw with an unjust penalty. But Dobbie does not expect this to have impacted on Celtic’s semi-final preparations this week. Indeed, Rodgers used familiarity to breed success during two years in charge at Swansea.

“Brendan didn’t change for any game,” says the 34-year-old. “The work he puts in from Monday to Saturday doesn’t change no matter who the opposition is. And the work he puts in to preparing his team for a game is unbelievable.

“Even when you weren’t in the squad, training was that good that you didn’t just turn up and feel annoyed because you knew you weren’t going to be playing in the next game. It was enjoyable – he made it enjoyable and made you want to work hard. He never said: ‘You’re not with us.’ He never put you to the side.”