Johnny Sexton and Jamie Heaslip rise to the top as Leinster cream Ulster

And the beat goes on, and on, and on.

And the beat goes on, and on, and on. Ulster won four must-win games in a row to get into the Guinness PRO12 semi-final. When they had to beat Leinster, they fell short. Then they fell off a cliff. Johnny Sexton, who has by now added the best of Ronan O'Gara to his own reportoire, and Jamie Heaslip were excellent for Leinster. Isa Nacewa was his old, brilliant self. 13-11 at the break but an arcing Garry Ringrose run had Ulster in trouble. He found Ben Te'o and his perfectly time offload - taking three men out - left Heaslip one-on-one with Paddy Jackson. Roadkill for the charging No.8. When the game was slipping away, with Ulster 20-11 up, Leo Cullen brought Sean Cronin and Tadhg Furlong onto the pitch. Two Ireland internationals and Ulster had no answer. 30-11 with minutes to play and Craig Gilroy got a consolation that may yet get him on a flight to South Africa this summer. The first half was a story played out impeccably to a decades-old script. Leinster were clinical, Ulster were dogged. Replace the names, tighten the jerseys and add kilos to each man out there but this was still Leinster v Ulster. In Dublin. Jamie Heaslip and Johnny Sexton reminded everyone of their class by, in turns, making the big carries in the right places and ramping up the backline incursions. Six minutes in and when Ruan Pienaar failed to clear his twenty-two with a box-kick, Leinster pounced. They ran through the phases to draw white shirts in and Eoin Reddan pulled the trigger. Snap pass to Isa Nacewa and two men yet to beat. No hassle to the veteran as he jagged, weaved and stretched. 5-0 became 7-0 with a Sexton conversion. Ulster looked in deep trouble after only 13 minutes as two more Band-Aid tackles brought penalties that Sexton converted. Next score was crucial - as they always say - and it was for Pienaar. Two simple penalties within comfortable range and the northmen were back in it. In between, there was time for Luke Fitzgerald to remind us all of his talents and for Ben Te'o, fair or foul, to clatter every Ulster player in sight. The half ended with Ulster pressing and Pienaar, thoroughly cosy in attack, making the difference. His gains gave Ulster an overlap and Craig Gilroy finished smartly after umpteen TMO replays. No conversion but Ulster were back. It's the hope that kills the Ulster fans, though. That and Leinster.