Auva'a, Madigan, Boyle, Ryan, Hudson
Clark, Murphy (2)
Darren Hudson; Andrew Boyle, Colm O'Shea, Noel Reid, Fionn Carr; Ian Madigan, John Cooney; Jack McGrath (for Sexton 80), Aaron Dundon, Jamie Hagan; Tom Denton, Damian Browne; Ben Marshall (for Browne 57), Shane Jennings (capt), Leo Auva'a
Thomas Sexton (for Dunson HT), Jack O'Connell (for McGrath 59), Martin Moore (for Hagan (59), Dominic Ryan (for Marshall HT), Jordi Murphy (for Jennings 65), Luke McGrath (for Hudson 77), Cathal Marsh, Brendan Macken (for O'Shea 73), James Tracy, Sam Coghlan-Murray (for Boyle 59)
Rob Cook; Shane Monahan, Tim Molenaar, Billy Twelvetrees, Ian Clark; Tim Taylor, Dave Lewis; Yann Thomas, Darren Dawidiuk, Shaun Knight; Tom Savage (for Brown 65), Alex Brown (capt); Peter Buxton (for Kalamafoni 65), Andy Hazell, Sione Kalamafoni
Koree Britton (for Dawidiuk 52), Dan Murphy (for Thomas HT), Dario Chistolini (for Knight HT), Will James (for Savage 50), Gareth Evans (for Buxton (50), Dan Robson (for Lewis HT), Martyn Thomas (for Cook HT), James Simpson-Daniel (for Monahan, 42), Rob Langley (for Hazell 65), Tommaso D'Apice (for Britton 80)
A succession of turnovers or penalties conceded saw several scoring opportunities slip away and it proved to be the difference between the two teams.
In contrast, Leinster crucially scored from their only two real visits to the Gloucester 22 in the first half when they were playing in to the wind.
However, nothing is won in preseason and there were plenty of positives for Davies and the rest of his coaching staff to focus on as well as plenty of areas to improve on.
The new signings showed up well. Sione Kalamafoni carried well, Rob Cook kicked his goals, Billy Twelvetrees grew more influential as the game progressed and Shane Monaham clearly relished his return to Ireland until a blow to the face saw him withdrawn.
Defeat is always disappointing but nothing is won or lost in preseason and next weekend, against the Cardiff Blues, will see the perfect opportunity to bounce back.
Gloucester supporters were treated to an early look at Rob Cook's unique kicking style as Leinster were penalised for not releasing and the full back shrugged off the wolf whistles from the home crowd to open the scoring.
It was a lively start from Gloucester who were working the phases well and looking to move the ball wide but a couple of frustrating penalties conceded at the ruck area prevented any further inroads taking place.
Leinster, in stark contrast, scored from their first real attack as a pair of penalties established good field position in the Gloucester 22.
Good work from the pack softened up the fringe defence and big number eight Leo Auva'a crashed over from close range. Ian Madigan added the conversion.
Gloucester hit back impressively, remaining patient and working the phases to force an attacking scrum in the home 22 in front of the posts.
They could have gone either way but Ian Clark took the ball in the fly half position and skipped past a tackle before diving over for his team's first try. Cook converted well to move Gloucester back in front. 10-7 after 19 minutes.
Gloucester almost scored again straightaway as Lewis rolled a lovely kick in to touch near the Leinster line and Alex Brown nicked the lineout to set up a great chance.
But referee Rolland's interpretation of the breakdown wasn't meeting with Gloucester's approval and another penalty killed that chance and allowed the home team to escape.
And they duly profited as an overthrown lineout bounced kindly into fly half Madigan's hands. He hit the line at pace and scampered home untouched from 25 metres before converting his own try.
14-10 to Leinster and Gloucester could feel more than a tad aggrieved at recent events.
But the Cherry and Whites again responded well and Dave Lewis very nearly caught the home defence napping with a quickly taken tap penalty.
However, Leinster just held out despite being under real pressure and went in to half time with their lead intact.
It had been a frustrating 40 minutes. Gloucester looked as though they were moving smoothly through the gears on several occasions only to give away a frustrating penalty.
Meanwhile, Leinster had defended with real spirit and executed two real smash and grab raids on the Gloucester line.
The home team would now play with the benefit of the wind behind them so a tough second half lay ahead for Gloucester.
A good start was required but it turned out to be just the opposite. Auva'a took a high ball and powered into the Gloucester 22 before Madigan torpedoed a cross kick to the unmarked Andrew Boyle who scored with ease. Madigan converted for 21-10.
It was time to dig deep and the initial response was impressive as Gloucester again stayed patient to create the merest of openings and Dan Murphy muscled his way over from close range to get his side back in it at 21-15.
Out of necessity Gloucester were keeping things tighter and a host of replacements gave the pack fresh momentum. James Simpson-Daniel also looked threatening but the breakthrough remained elusive.
Instead it was Leinster who struck next as a lost lineout hurt Gloucester and allowed Dominic Ryan to break a tackle and score from close range. Madigan again converted for 28-15.
Another error, this time a dropped up and under, promptly led to another Leinster try as full back Hudson touched down unopposed for a 33-15 lead.
There was still fight in Gloucester and patient build up play saw Billy Twelvetrees put prop Dan Murphy in under the posts for his second with Taylor converting.
Gloucester so very nearly added another late try, but it was too little too late as the home team held on for the win, triumphing by 33 points to 22.