Pro14: Leinster score six tries in a 40-7 win over Ulster

Hooker Sean Cronin scored two tries for Leinster in the opening 12 minutes at the RDS

Ulster's decision to send a youthful squad to face Pro14 holders Leinster backfired dramatically at the RDS.

Ireland hooker Sean Cronin scored twice in the opening 12 minutes as Leinster cruised to a bonus-point 40-7 win.

Jamison Gibson-Park, Conor O'Brien and Andrew Porter also scored before a late penalty try ended a one-sided contest.

Adam McBurney's try and a conversion by Johnny McPhillips were the only points for Ulster, who gave second-half debuts to Bruce Houston and Caleb Montgomery.

Leinster have stretched 19 points clear at the top of Pro14 Conference B but Ulster have dropped from second to fourth following Benetton's shock win over Glasgow and Scarlets' victory against Dragons.

Ulster have not won an interpro derby away from home since December 2015

Cronin sets the tone

Leinster were punished for an ill-disciplined display against Munster at Thomond Park in round 12 and the defending champions were determined to lay down an early marker as they raced into a 14-point lead in as many minutes.

An early attack, bristling with aggressive carries and ferocious clear-outs, went through 25 phases before Cronin burst between two tacklers to score under the posts.

The Ireland hooker was back on the scoreboard minutes later when the impressive Conor O'Brien broke a tackle and cleverly kept the ball alive before Cronin timed his run for the line perfectly, leaving Dave Shanahan powerless to prevent him scoring.

Leinster's poor discipline again allowed their opponents back into the game as Ulster were able to work their way into a scoring position and McBurney spun away from a powerful line-out maul to touchdown for a try that was brilliantly converted by McPhillips from the left touchline.

O'Brien try the highlight

From the restart, Leinster showcased their clinical attack with a superb try that wrestled momentum back from the visitors.

Rob Kearney jumped highest to win Ciaran Frawley's deft restart and it took just two passes to work the ball left to Conor O'Brien.

The outside centre still had plenty of work to do but he punished some poor Ulster defending as he weaved and dodged past four attempted tackles for a stunning score.

McPhillips missed a long-range penalty effort and passed up another shot at goal before Leinster secured a bonus point in first-half stoppage time when Porter muscled his way over for a forward-dominated try.

Leinster centre Conor O'Brien scored the pick of his side's tries

Ulster limit the damage

An injury to loose-head prop Kyle McCall at the start of the second-half robbed Ulster of the chance to mount a fight back but Leinster rarely looked under pressure as their forward pack controlled the contest.

The introduction of an all-new front-row gave the Leinster scrum an extra edge that led to Gibson-Park darting over from close range.

Academy duo Houston and Montgomery both made their Ulster debuts in the second-half while Leinster second row Oisin Dowling also made his first senior appearance as the pace of the game eased.

The visitors briefly threatened a consolation score following a thrilling break by James Hume but it was the hosts that finished on the attack as another series of powerful scrums were eventually rewarded with a penalty try by referee Andrew Brace.

'Ulster should have been closer than that'

Ex Ulster forward Tony McWhirter on BBC Radio Ulster: "This was a different performance from the one in Thomond at the start of the season [a 64-7 loss to Munster] where Ulster rolled over and had their bellies tickled. Tonight they've been beaten by 33 points, has the scoreline been a reflection? Possibly in the end it has been but certainly in the first half - although it was a 19-point gap at half time - Ulster should have been closer than that and there's a difference now between this Ulster side and the start of the season. Dan McFarland has his players fighting for every inch and you saw some of that tonight.

"It was always going to be difficult - Leinster are a class side from one to 12 - and the young Ulster players have to learn from this."

Leinster: R Kearney (capt); A Byrne, C O'Brien, N Reid, B Daly; C Frawley, J Gibson-Park; J McGrath, S Cronin, A Porter; R Molony, M Kearney; J Murphy, S Penny, M Deegan.

Replacements: J Tracy, E Byrne, M Bent, O Dowling, C Doris, H O'Sullivan, R Byrne, J O'Brien.

Ulster: M Lowry; R Lyttle, D Cave, J Hume, A Kernohan; J McPhillips, D Shanahan; K McCall, A McBurney, W Herbst; M Dalton, A O'Connor (capt); G Jones, S Reidy, N Timoney.

Replacements: J Andrew, A Warwick, T O'Toole, C Montgomery, C Ross, J Stewart, B Houston, P Nelson.

Referee: Andrew Brace (IRFU)