European champions Leinster edged out the Newport Gwent Dragons in a tight tussle at the RDS, with Isa Nacewa their only try scorer and Jonathan Sexton and Shaun Berne kicking 18 points between them.

Nathan Hines and Eoin Reddan made their competitive debuts for Leinster in a workmanlike home win over the Dragons.

The introduction of the pair midway through the second half – along with Hines’ Lions colleague Gordon D’Arcy – helped Michael Cheika’s side battle to their first victory in this season’s Magners League.

Despite losing Gavin Thomas and Ashley Smith to the sin-bin in the first half, the Dragons were just 9-6 behind until free-running full-back Isa Nacewa burst clear for Leinster’s only try.

His opposite number Martyn Thomas replied with a well-worked try and while a penalty from James Arlidge cut the gap to six points again, Leinster were able to seal the result with a late drop goal from Shaun Berne.

Boosted by last week’s home defeat of Ulster, the Welshmen showed confidence on the ball early on with Wayne Evans building momentum with his forwards.

Debutant winger David Kearney was sprung for a 40-metre gallop that drew the 15,145-strong crowd’s approval, but Leinster struggled to capitalise on their breaks.

The deadlock was broken on 14 minutes when Jonathan Sexton slotted the first of his four penalty successes – only for Arlidge to response quickly, after Kevin McLaughlin was pulled up for a binding offence.

Thomas’ sin-binning for killing the ball preceded another Sexton penalty. Down to 14 men, the Dragons maintained possession impressively with Smith and Grant Webb heavily involved.

The visitors engineered a drop goal shot, which Arlidge pushed wide, and a dinked kick in the left corner from Richard Fussell came to nothing.

The nip-and-tuck nature of the game continued. A forceful run through the middle from man-of-the-match Sean O’Brien lifted Leinster and Cian Healy was inches away from nabbing a try.

Smith walked, seven minutes before the break, for spoiling at a ruck. Leinster had to settle for another Sexton kick and the Dragons’ determined drives forward were rewarded on the stroke of half-time with an Arlidge drop goal.

An eye injury prevented Dragons stand-in captain Luke Charteris from returning for the second half and they needed flanker Thomas to produce a crucial steal as Leinster piled forward.

The Dragons’ resistance was finally broken though, on 54 minutes.

The try was worth the admission price alone – a sumptuous wrap-around between Sexton and Berne set D’Arcy free near halfway and his well-placed pass put Nacewa thundering past Fussell and over from 30 metres out.

Berne tagged on a drop goal soon after and Leinster’s lead was out to 17-6.

Credit to the Dragons, they maintained their composure and hit back when Tom Riley tied up D’Arcy near the Leinster 22, allowing Fussell the time and space to put full-back Thomas through for an unconverted try.

Sexton steadied the home ship with a close range penalty but the Leinster out-half saw yellow for a ruck offence and Arlidge kicked the Dragons to a likely bonus point.

However, Leinster pressed on and Berne’s final-minute drop goal confirmed the Irish province’s tenth successive win at the RDS.

Speaking after the game, a pleased Sean O’Brien said: "It was a very important result. We had to bounce back after last week’s defeat to the Scarlets and it was a good win, so we’re happy.

"With so much competition in the pack I’m not that fussed where I play. So long as I play!

"We stepped it up a gear (after the replacements came in) and we’re trying to build all the time. So we’re happy, but we know that we have areas to improve."