London Irish clinched third place in the Guinness Premiership and a play-off clash at Harlequins thanks to a five-try haul at Worcester.

It was not easy for the Exiles as the Warriors put up stern resistence in the first half but were overcome when Irish upped the pace and grabbed a bonus point after the interval.

The Exiles' plan at the start was simple. Two points and they were in the play-offs for the first time in three years, regardless of what happened to Sale.

The Sharks, who are appealing a one-point deduction for fielding an ineligible player, needed a five-pointer at home to Northampton.

Worcester rugby director Mike Ruddock made numerous changes to the side which started their shock backs-to-the-wall 13-6 victory at Gloucester last Tuesday as he had one eye on their European Challenge Cup semi-final against French outfit Bourgoin next Saturday.

Irish head coach Toby Booth, meanwhile, had skipper Bob Casey back in the second row.

Right from the start Worcester were under the cosh and their scrum was under huge pressure, as was the case at Kingsholm.

That had to tell and, when flanker Steffon Armitage rumbled into the home 22, he set up a sustained attack which ended with wing Sailosi Tagicakibau going over unopposed for a converted try.

Worcester, though, managed to stem the tide and produced a try when scrum-half Matt Powell fed hooker Chris Fortey to crash over and set a simple conversion for fly-half Joe Carlisle.

A penalty each from Carlisle and England full-back Delon Armitage kept the scores level at 10-10 when the interval arrived although Worcester nearly went in ahead, but number eight Netani Talei made a double-movement and gave Irish a clearing penalty.

With other matches going the Exiles' way, they decided to go for a bonus-point win to land third place and an away draw against second-placed Harlequins rather than a trip to Leicester's Welford Road.

And big number eight Chris Hala'ufia provided their second touchdown, an old-fashioned pick-up and drive from the back row at an attacking scrum.

By the 58th minute, Irish were all but there as scrum-half Paul Hodgson sneaked down the blindside of a ruck for their third touchdown and, after a Armitage burst up the middle, the ball found its way to flanker Declan Danaher out wide on the right to rumble over for the bonus-point try.

Worcester were shot and Irish began to enjoy themselves, even allowing 37-year-old Lion Mike Catt to come on with 20 minutes left.

The game was over when Adam Thompstone intercepted for London Irish's fifth try but Worcester never gave up and finally got a deserved consolation when replacement George Crook went over in the last seconds.