Steve McColl's late try capped a Gloucester victory from an error-strewn Aviva Premiership tussle at the Madejski Stadium.
The visitors made hard work of defeating a poor London Irish side but tries from Henry Purdy and McColl proved sufficient as Gloucester departed with a 21-9 success.
Greg Laidlaw kicked three penalties and a conversion to complete the Gloucester scoring, with three penalties from Shane Geraghty being Irish's only reply.
Irish could have been closer on the scoreboard but Geraghty declined to kick a number of other penalties, in favour of more attacking options, but the home side lacked the precision at crucial times to get over the try line.
Both teams welcomed back a number of international players. James Hook and Laidlaw returned at half-back for Gloucester with Richard Hibbard and Sione Kalamafoni resuming up front.
After last week's home defeat to Bath, Irish considerably strengthened their pack with Geoff Cross, Jebb Sinclair, Blair Cowan, Ofisa Treviranus and Kieran Low all in the starting line-up. However their captain, George Skivington, was a late withdrawal for the second week running, following a setback to his recovery from a shoulder injury. Sean Cox came into the team with Geraghty taking over the captaincy.
The teams appeared equally matched in the opening 10 minutes before Irish had the first chance for points. They were awarded a kickable penalty, with Geraghty opting for an attacking line-out, but a knock-on by the hosts emphasised he had taken the wrong decision.
The first 20 minutes were both scoreless and largely featureless as the sides struggled to bring any continuity to their game. There were a plethora of knock-ons, resulting in scrums and frequent resets which brought little entertainment to a sparse crowd.
A poor clearance kick from Chris Noakes was collected by Gloucester full-back McColl, whose kick ahead and regather gave Gloucester a platform 10 metres out for the Irish line. Gloucester had two attacking scrums but at the second conceded a penalty, allowing Irish to relieve the pressure.
Gloucester continued to have the better of the second quarter. A clever cross-field kick from Hook was collected by Purdy to test the home defence. It did not result in the first try but five minutes from half-time Laidlaw put his side in front with a penalty.
With the last kick of the half, Geraghty attempted a penalty from inside his own half. It fell short and wide to leave Irish trailing 3-0 at the interval.
Four minutes after the restart, Irish suffered two blows. First they lost outside-half Noakes with an injury, to be replaced by Eoin Griffin, before Laidlaw kicked his penalty to extend Gloucester's lead.
From nowhere, Gloucester scored an excellent try. Irish lost possession at a maul on halfway, which enabled Mark Atkinson to make a break and neatly offload to McColl.
The full-back gave Purdy his opportunity and he raced away to hold off two covering defenders for the score, which Laidlaw was unable to convert.
Irish immediately reacted by making three substitutions, with Cross, Low and Scott Steele all departing. Dan Leo, Halani Aulika and Darren Allinson replaced them and the move soon paid dividends as two Geraghty penalties in quick succession put the home side on the scoreboard.
Irish fell further behind when Laidlaw kicked his third penalty after the hosts seemed unfortunate to concede a scrummage penalty. Another successful penalty from Geraghty effectively nullified that and kept Irish still in contention at 14-9 down at the end of the third quarter.
Geraghty declined two kickable penalties as Irish searched for a crucial try but again they lost a vital line-out before conceding a penalty to allow Gloucester to clear the danger.
With six minutes remaining, Gloucester secured victory when Hook's chip ahead was collected by McColl for a match-clinching try, which Laidlaw converted.
There was a late yellow card for Gloucester lock Tom Savage, but with Irish continuing to make handling errors there was little chance of taking any advantage.