Sailosi Tagickibau scored two tries as London Irish cruised to a 40-10 win against Gloucester at Madejski Stadium in the Guinness Premiership on Sunday.
Ryan Lamb contributed 20 points against his former club as the Exiles racked up a bonus point for scoring four tries.
Delon Armitage, England's most dynamic performer last season, gave England an injury scare left the pitch in the 61st minute clutching his left wrist after scoring his teams first try.
With Toby Flood, Riki Flutey and Mike Tindall already in the treatment room, England manager Martin Johnson can ill afford any further injuries to his back line.
The full-back's departure took the shine off an otherwise excellent afternoon for Irish, who recorded their first win of the new league campaign.
Lamb took revenge on former club Gloucester by masterminding the outcome and claiming the man-of-the-match award.
Drummed out of Kingsholm as part of Gloucester's summer exodus, the Exiles fly-half showed them what they were missing with an authoritative display.
The 23-year-old finished with a 20-point haul, although he was given a comfortable ride by a dominant Irish pack.
Winger Tagicakibau ran in two tries and Armitage also touched down, while referee Dean Richards awarded a late penalty try.
Gloucester were effectively out of contention by the interval, trailing 23-3, and apart from a bright spell in the second half when winger Charlie Steeples crossed they were well off the pace.
Irish's back row were rampant early on, Steffon Armitage surging down the left touchline until he was halted by Olly Morgan.
Then it was the turn of Chris Hala'ufia and Declan Danaher to maraud into space, stretching Gloucester's defence and helping create a three-man overlap.
Lamb, who had earlier exchanged penalties with Nicky Robinson, executed a perfect crossfield chip but Armitage spilled the ball with the line at his mercy.
The England full-back had to wait only until the 25th minute to make amends, however, as he capitalised on a wicked bounced that deceived Rory Lawson and Morgan.
Tagicakibau started the move with a lively run and chip ahead that Armitage hacked on before touching down as Lawson and Morgan dithered.
Lamb added the conversion and a second penalty while wayward kicking by Robinson ensured six points went begging for Gloucester.
Holes were being punched in Gloucester's defence with increasing regularity, Paul Hodgson sending Chris Hala'ufia through before Elvis Seveali'i was tackled without the ball by Sharples as Irish threatened to score again.
Sharples was sent to the sin-bin and Lamb's growing influence began to tell as he helped set up a try for Tagicakibau in the left corner, which he converted.
A fourth Lamb penalty shortly into the second half hammered another nail into Gloucester's coffin, though the sin-binning of Hala'ufia for killing the ball offered some hope.
Ferocious tackling from Irish, led by hooker Danie Coetzee, kept their line intact as the visitors probed for their first try.
They finally breached the whitewash when Sharples capitalised on a missed tackle by Hodgson to dash home with Robinson landing the conversion.
But the fightback soon faded, Alasdair Dickinson receiving a yellow card for a line-out offence before referee Richards awarded Irish a penalty try as Gloucester struggled at a scrum.
Tagicakibau had the last say in a thoroughly one-sided clash, skipping in to secure the bonus point with Lamb converting.
A large fight broke out in the closing seconds and Gareth Delve and George Stowers were eventually sent to the sin-bin, making it six yellow cards for the match.
For London Irish:
Tries: Armitage, Tagicakibau 2, Penalty Try
Cons: Lamb 4
Pens: Lamb 4
Yellow cards: Sharples (Gloucester - 34th min), Hala'ufia (London Irish - 50th min), Qera (Gloucester - 68th min), Stowers (London Irish - 78th min), Delve (Gloucester - 78th min)
London Irish: 15 Delon Armitage, 14 Adam Thompstone, 13 Elvis Seveali'i, 12 Seilala Mapusua, 11 Sailosi Tagickibau, 10 Ryan Lamb, 9 Paul Hodgson, 8 Chris Hala'Ufia, 7 Steffon Armitage, 6 Declan Danaher, 5 Bob Casey (c), 4 Nick Kennedy, 3 Paulica Ion, 2 Danie Coetzee, 1 Clarke Dermody.
Replacements: 16 Dan Murphy, 17 James Buckland, 18 Faan Rautenbach, 19 Andy Perry, 20 George Stowers, 21 Peter Hewat, 22 Peter Richards, 23 Alfredo Lalanne.
Gloucester: 15 Olly Morgan, 14 Charlie Sharples, 13 Tim Molenaar, 12 Eliota-Fuimaono-Sapolu, 11 Tom Voyce, 10 Nicky Robinson, 9 Rory Lawson, 8 Gareth Delve (c), 7 Andrew Hazell, 6 Alasdair Strokosch, 5 Alex Brown, 4 Dave Attwood, 3 Greg Somerville, 2 Scott Lawson, 1 Alasdair Dickinson.
Replacements: 16 Darren Dawiduik, 17 Nick Wood, 18 Pierre Capdevielle, 19 Marco Bortolami, 20 Akapusi Qera, 21 Dave Lewis, 22 Freddie Burns, 23 James Simpson-Daniel.
Venue: Madejski Stadium
Referee: Dean Richards