Gloucester tasted defeat in the A League at Kingsholm on Monday evening as Harlequins produced a second half try scoring burst to overcome a half time deficit and emerge easy 45-14 winners.
The home side had competed well in the first period and went in with a deserved lead.
However, it was already obvious that Quins had the advantage up front with a number of gnarled veterans with Premiership experience enjoying themselves against a Gloucester eight who had barely met each other before kick off.
Cannily led behind the scrum by the likes of Steve So'oialo and Nils Mordt, Quins always had a little too much for a spirited Gloucester side and it was always a question of when rather than if.
Gloucester drew first blood after Freddie Burns was taken out late having put in a chip ahead. Burns dusted himself off and chipped over a straightforward penalty.
Quins responded well and pegged Gloucester back with a series of attacks near the line with the home defence having to work overtime to keep Quins at bay.
The visitors appeared to have the edge up front at this point and almost fashioned a try for George Lowe on the crash ball but the centre was held up over the line. However, the pressure eventually told and flanker Luke Wallace crashed over for the score. Rory Clegg converted and Quins took a 7-3 lead after 18 minutes.
Gloucester came back well, following up a hack through from number eight Phil Burgess. Jordi Pasqualin and Freddie Burns almost jinked their way through but had to settle for a Burns penalty.
It had been a good spell for Gloucester and they capitalised with a fine score. Burns changed the direction of attack and linked with Henry Trinder who drew the last man for Jonny May to finish well in the corner. 28 minutes gone and Gloucester were up 11-7.
Clegg had a chance to hit back but he drilled a straightforward penalty attempt wide however the Quins pack swiftly reimposed themselves to pile on the pressure until their over eagerness got the better of them and they conceded a free kick for an early charge at the scrum.
And Gloucester's bravery in defence was rewarded as they moved upfield, Henry Trinder almost wriggled free but Burns added his third penalty as Quins offended at the ruck to send Gloucester into half time with a 14-7 lead.
The Quins pack were quickly back into their stride from the restart, driving 40 metres downfield before Steve So'oialo made the telling break and Nils Mordt took the scoring pass. Clegg was wide right with the conversion but Quins were right back in it at 14-12.
So'oilalo then caught the home defence napping as he scampered over from a quickly taken tap penalty after more pressure and had shipped ten points in a 5 minute spell.
After a flurry of changes, the Quins pack finally got their reward with a well executed catch and drive resulting in a score for prop James Johnston and Clegg finally got his kicking sights adjusted to convert. At 24-14, Quins looked to have taken a decisive lead.
Gloucester threatened but England Sevens winger Josh Drauiniui was next to cross for Quins as Gloucester made a mess of fielding a grubber kick near their own line and Clegg added the extras.
Drauiniui then moved smoothly through the gears to finish off a move set up by his own initial break and Clegg,who was by now kicking everything, converted from the touchline.
The final quarter simply drifted along with neither side able to make any real inroads although Reuben Haile's interception lifted the home crowd but Gloucester couldn't finish the move off.
With time virtually up, Gloucester kept plugging away but the Quins defence was resolute and salt was rubbed into Gloucester wounds as their final attacking move resulted only in a turnover and a length of the field try for Quins replacement winger Chris Rose.