Admittedly, the Cherry and Whites had spurned some scoring opportunities, but were well in the game shortly after half time, with Irish leading 10-9.
The home team then stunned Gloucester with two rapid tries, the second a real sickener due to its flukey nature, and it looked as though the game had gone.
However, what followed was a comeback that not even the most ardent Gloucester would have seen coming.
Firstly Dan Murphy, against his former club, burrowed over from close range and Freddie Burns added a second.
Burns, who kicked 25 points here in the Aviva Premiership earlier this season, then continued to torment the Exiles by continuing the put the ball between the uprights to extend the lead to 29-22.
There were some nervous moments in the final few minutes, as the home team threw the kitchen sink at Gloucester to try and rescue something from the game.
However, Gloucester held out to clinch the win and take a two point lead at the top of pool one with the reverse fixture to follow at Kingsholm next weekend.
The day got off to a less than auspicious start for Gloucester as hooker Huia Edmonds was ruled out in the warm up. Darren Dawidiuk came in for the Australian.
And, then the home side, coming out of the blocks quickly, took an early lead.
Irish won a scrum from the kick off, and kept the ball patiently through several phases, stretching Gloucester left and right.
Gloucester looked to be coping well until Sailosi Tagicakibau stepped off his right foot to beat a tackle and score. Humphreys added the extras. Not the ideal start for the Cherry and Whites.
However, there was an instant response as Burns kicked a penalty for Gloucester's first points for the day, which was followed by a morale boosting run from Sione Kalamafoni.
A penalty followed but Burns, in such a fine vein of kicking form recently, was narrowly wide with his long range effort.
Burns then pinned Irish back deep in their own 22, but the home side moved downfield and turned down a kickable penalty in favour of a quick tap. But the Gloucester defence was alert and snuffed out the danger.
Nigel Davies' side then enjoyed a good few minutes with ball in hand, without ever really looking like breaking through. But Gloucester looked good with ball in hand and were at least asking questions.
However, it was defensive qualities that were called for next, as Gloucester just held out after a spell of pressure from the home side, indebted to a timely turnover near the line and a wasted two on one by Irish.
Gloucester looked to have escaped unscathed, but immediately went to ground in support of the tackled man to concede a penalty. Ian Humphreys made it 10-3 after 26 minutes.
Once more, Gloucester bounced back well. Darren Dawidiuk peeled off a maul to set up a great position in the Irish 22. A knock on followed, but Irish were penalised at the scrum and Burns duly made it 10-6.
Gloucester finished the half the stronger. Shane Monahan made a great break from inside his own half, but was just hauled down by the cover and the chance was gone.
So, the home team led 10-6 at half team, and it was very much in the balance. Gloucester had bounced back well after a poor start and played some good rugby without being able to finish off the chances they created.
You got the impression that the Cherry and Whites just needed to convert one of these opportunities, and they would be in business. They had certainly showed the ambition thus far.
The second half started well as the likes of Kalamafoni and Savage quickly took the game to the home side. The home team held out but only at the expense of a penalty from Burns, which narrowed the gap to 10-9.
The momentum was shortlived. Irish won a lineout in the Gloucester 22 and unleashed a slow, steady rolling maul from which prop Halanu Aulika broke and slipped a tackle to touch down. Humphreys converted for 17-9.
It was a blow for Gloucester, and a lesson in taking chances.
And, bad promptly went to worse. Gloucester were on the attack when Freddie Burns tried to slide a grubber kick in behind the advancing defensive line.
It was the right tactic but unlucky in its execution. It hit an Irish leg, then bounced kindly for Anthony Watson who gathered and ran it home from his own 10 metre line despite Dan Robson's valiant chase.
At 22-9, Gloucester needed to respond and quickly. Murphy, Harden and Morgan were all sent into the fray and were quickly followed by Tindall.
And it was the forwards who dug deep. Sharples was held up over the line after good work by the pack. However, Murphy burrowed over for his third try in five competitive games after the next scrum. Burns converted for 22-16.
Gloucester were suddenly on fire, with Freddie Burns making huge ground with ball in hand. Bryn Evans was sinbinned as the pressure mounted and the Irish resorted to desperate measures to defend their line.
The Cherry and Whites scented blood and, even though a catch and dive was thwarted, Burns was given a metre of space after more pressure and dived over to score. He duly converted his own try to give Gloucester a 23-22 lead.
The excitement grew. Dave Lewis made a superb break and found Mike Tindall on a brilliant support line. Tindall was hauled down just short, but a penalty was awarded and Burns extended the lead to 26-22.
Another penalty for Burns followed, and the home crowd started to make real disgruntled sounds as they sensed the game slipping away.
Credit to the Exiles. Although they had been rocked by the events of the previous few minutes, they refused to throw in the towel.
Gloucester were forced to defend doggedly in the final few minutes. However, Nigel Davies' side had fought tooth and nail to regain the lead and they were in no mood to give it up.
|London Irish Score Card|
|Gloucester Rugby Score Card|