London Irish ensured they would go into the Heineken Cup on top of the domestic summit as they got past Leeds Carnegie 40-24 on Saturday.
Three penalties from Ryan Lamb, who ended with a personal haul of 18 points, and a converted try from hooker James Buckland helped the Exiles to a 16-7 advantage. Ceiron Thomas crossed for the visitors and converting his own try.
The home side added further scores through replacement wing Sailosi Tagicakibau (2) and George Stowers, meaning tries from Hendre Fourie and Luther Burrell were not enough.
After a scrappy start to the match, the Irish had the first chance to open the scoring after six minutes when the visitors were penalised but Lamb was short with his kick from 45 metres out, and the fly-half was also off the mark with an effort from the other side of the field.
Leeds had the better of the first quarter with some neat inter-passing among the forwards building up some pressure in the home 22 but they frequently incurred the displeasure of the referee, conceding seven penalties in the first 15 minutes.
Immediately from the restart back came Leeds to take a surprise lead.
Their forwards again rumbled into the home 22 and from a ruck 10 metres out Ceiron Thomas ran strongly to score under the posts with the outside-half converting his own try.
At long last Irish found some momentum to their game putting Leeds under severe pressure, and once again the visitors offended and Lamb kicked the simple penalty.
Minutes later Thomas had the chance to restore his side's advantage but his 45-metre penalty attempt went wide.
Leeds were being penalised with monotonous regularity and it became inevitable that a yellow card would be issued.
It fell to Fourie to receive it for diving over at a ruck and Irish took immediate advantage with a close-range try from Buckland which Lamb converted, and then with the last kick of the half he kicked a penalty to give the home side a somewhat undeserved 16-7 lead.
Leeds started the second half strongly and Thomas reduced the arrears with his first penalty after 44 minutes but Lamb replied with a three-pointer of his own soon after.
Irish then woke from their slumbers and produced their best movement of the match which resulted in replacement Tagicakibau beating a couple of defenders to score. Lamb converted that try and another one soon followed from Stowers which put Irish out of sight.
The visitors continued to battle and were rewarded with a try from Fourie converted by Thomas, but they faced a daunting last eight minutes when Rhys Oakley became another casualty to the sin bin.
Tagicakibau scored his second try which Chris Malone converted.
Burrell picked up a consolation try for the visitors which Christian Lewis-Pratt converted with the last kick of the game.
For London Irish:
Tries: Buckland, Tagicakibau 2, Stowers
Con: Lamb 3, Malone
Pen: Lamb 4
For Leeds Carnegie:
Tries: Thomas, Fourie, Burrell
Con: Thomas 2, Lewis-Pratt
London Irish: 15 Delon Armitage, 14 Topsy Ojo, 13 Seilala Mapusua, 12 Daniel Bowden, 11 Jonathan Joseph, 10 Ryan Lamb, 9 Paul Hodgson, 8 George Stowers, 7 Declan Danaher, 6 Kieran Roche, 5 Bob Casey, 4 Nick Kennedy, 3 Alex Corbisiero, 2 James Buckland,1 Clarke Dermody (c).
Replacements: 16 David Paice, 17 Max Lahiff, 18 Faan Rautenbach, 19 Matt Garvey, 20 Jonathon Fisher, 21 Sailosi Tagicakibau, 22 Elvis Seveali'i, 23 Darren Allinson.
Leeds Carnegie: 15 Leigh Hinton, 14 Mike Stephenson, 13 James Tincknell, 12 Luther Burrell, 11 Semi Tadulala, 10 Ceiron Thomas, 9 Scott Mathie, 8 Danny Paul, 7 Hendre Fourie, 6 Kearnan Myall, 5 Marco Wentzel (c), 4 Sean Hohneck, 3 Juan Gomez, 2 Andy Titterrell, 1 Mike Macdonald.
Replacements: 16 Steve Thompson, 17 Gareth Hardy, 18 Miguel Alonso, 19 Tom Denton, 20 Rhys Oakley, 21 Warren Fury, 22 Christian Lewis-Pratt, 23 Henry Faafili.
Referee: Greg Garner