SECOND half tries from Pete Richards, Olivier Azam and James Forrester continued Gloucester's winning start in the Guinness Premiership against Harlequins.
But they needed all their togetherness, composure and instinct to get the better of a Harlequins side who at one stage held a 13-6 lead and then rallied superbly towards the end of a error-strewn but absorbing contest.
Until half-time, Gloucester had been distinctly second best as Quins, inspired by number eight Mark Easter and a whole host of his forward cronies, laid seige in Gloucester's territory and were well worth their substantial lead.
Gloucester had been all at sea. Wrong options were taken, possession was forced and they worked off very little front foot ball to make it a far more difficult afternoon than it perhaps should have been.
Although Willie Walker gave them a 3-0 lead with a third minute penalty, Quins hit back to dominate the middle and end sections of the half. Although former All Black Andrew Mehrtens missed an early penalty, he settled down with three points when Christian Califano was penalised for a high tackle on Easter.
Mehrtens then slotted another penalty after 25 minutes as the hosts cranked up the pressure. There was plenty to admire in the efforts of Paul Volley and lock Nicolas Spanghero, while David Strettle also looked seriously threatening before he limped off with a leg injury.
And Quins got what they deserved immediately after Mehrtens' second penalty. From the re-start, scrum-half Steve So'oialo did a disappearing act down the right touchline past a thicket of Gloucester defenders and Spanghero was on hand to deliver the scoring pass to prop Ceri Jones, who somehow appeared on the right wing.
Their 13-3 advantage became 13-6 when Walker landed his second penalty but before the break Mehrtens ensured a 10-point cushion for the Quins when he slotted again after Gloucester were penalised for off-side.
If Gloucester had thought it would be a comfortable afternoon in the capital they were very much mistaken. But they awoke from their slumber immediately after the re-start and stung into life.
Andy Hazell, as busy and as destructive as anyone in a Gloucester shirt, almost scored when he took a Mehrtens pass on the 22 metre line but Walker landed the penalty to bring the visitors within a converted try.
And that try came two minutes later. A Gloucester scrum slithered round but James Forrester was able to get his pass away to Richards, five metres inside his own half. But the scrum-half had his tail up. He broke blind, skipped past the initial cover and brushed past tackles from Mehrtens and Gavin Duffy to snap and burst his way into the corner for a sensational try.
Walker's conversion tied the scores and then a 60th minute penalty got Gloucester's noses in front again at 19-16.
The tide was turning. Gloucester's forwards, pumped up and knocking defenders out of the way, were providing a platform for Richards and from the re-start, they scored again.
Richards found Anthony Allen who did wonderfully well to keep his composure and bring play into midfield with a mazy break. With play broken up, Gloucester controlled a ruck 25 metres out and Olivier Azam picked up, shrugged through the tackle of Tom Williams and smashed his way to the line.
The game had been broken right open and when Forrester broke off the tail of a scrum close to the line to score Gloucester's third try, a bonus point semmed a possibility.
However, mistakes still cost Gloucester dear. After Walker's kick-off went dead, Quins regrouped and launched a late rally that produced a very nice try for Simon Keogh after a lovely pass from Mehrtens but it was not enough and Gloucester could celebrate a second successive victory that will be crucial in the weeks to come.