London Irish 47-28 London Welsh
London Irish (19) 47
- Tries: Armitage 2, Aulika 2, Hala'ufia, Tagicakibau, Garvey
- Cons: Humphreys 6
London Welsh (15) 28
- Tries: Stegmann, Scott, Bateman
- Cons: Ross 2
- Pens: Ross 3
London Irish ran in seven tries for an ultimately comfortable win in the battle of the Premiership's bottom two.
The visitors shrugged off an early Guy Armitage try to take the lead as Seb Stegmann and Nick Scott went over.
However, two tries from prop Halana Aulika either side of the break and one from Chris Hala'ufia put Irish on top.
Two Gordon Ross penalties cut the lead, but Sailosi Tagicakibau, Matt Garvey and Armitage ended Welsh hopes before Greg Bateman claimed a consolation try.
Already relegated from the top flight, it was London Welsh's 11th successive Premiership defeat and meant they missed out on a rare seasonal double, having beaten their fellow Exiles 15-9 in Oxford last December.
Aulika's close-range double took his total to 11 tries for the season, and four in the last four games, but he was to be denied a hat-trick in the closing stages at the Madejski Stadium.
Welsh were only 19-15 in arrears at the interval after a half of entertaining, running rugby by both sides, but Aulika's second came shortly after the re-start, with Humphreys landing the conversion, one of six during the game.
Ross, making his 100th Premiership appearances, brought Welsh back within five points, only for the home side to hit them with a three-try burst which settled the outcome.
London Irish: Homer, Yarde, Armitage, Shingler, Tagicakibau, Humphreys, Allinson, Corbisiero, Paice, Aulika, Skivington (capt), Evans, Garvey, Treviranus, Hala'ufia.
Replacements: Lawson for Paice (51), Yanuyanutawa for Corbisiero (63), Halavatau for Aulika (58), Low for Evans (69), Danaher for Hala'ufia (46), Ojo for Shingler (69), Geraghty for Horner (69), Moates for Allinson (63).
London Welsh: Arscott, Scott, Stegmann, Parker, Caprice, Ross (capt), Keats, Bristow, Bateman, Ion, Corker, Kulemin, Cabello, Hills, Browne.
Replacements: George for Cabello (63), Joly for Ion (63), Tideswell for Bristow (66), Brown for Koulemine (63), Balding for Hills (11), Lewis for Parker (32), Davies for Keats (79), Ajuwa for Caprice (56).