England international Barkley landed four penalties and a conversion of James Simpson-Daniel’s 39th-minute try on his Gloucester European debut.

But Biarritz exposed enough chinks in Gloucester’s armour to suggest Pool Six could go to the wire, especially after Cardiff Blues’ demolition of Italian hosts Calvisano earlier today.

Gloucester did enough – but nothing more – to keep Biarritz at bay.

A poor game, punctuated by the fussy officiating of Scottish referee Peter Allen, never remotely threatened to move through the gears.

And Gloucester boss Dean Ryan must know there is a lot of work to be done before next Sunday’s Millennium Stadium clash with Cardiff.

Biarritz, despite a Jean-Baptiste Gobelet try and Julien Peyrelongue drop-goal and conversion, had to content themselves with no points from the match.

But they will head home safe in the knowledge their qualifying pool has a long way to run.

Gloucester handed Ryan Lamb the number 10 shirt for their biggest game since last season’s Guinness Premiership play-off clash against Leicester, while 2006 Heineken Cup runners-up Biarritz included England international flanker Magnus Lund.

Conditions were perfect for an attacking spectacle but Gloucester knew they could not afford to fall at the first hurdle.

And Barkley quickly calmed any nerves, kicking two penalties from distance during the opening eight minutes as Biarritz struggled to cope not only with the home side, but also a blinding setting sun.

Peyrelongue slotted a drop-goal to open Biarritz’s account, and they sensed another opportunity when Gloucester full-back Olly Morgan was sin-binned for a dangerous tackle on Damien Traille.

The hosts continued to monopolise possession, yet they ended a tense opening quarter just three points ahead, a situation that did little to appease the majority of their fans.

Barkley completed his penalty hat-trick 11 minutes before the break after Biarritz skipper Jerome Thion was yellow-carded for hands in a ruck.

France international Traille was narrowly wide with a long-range penalty attempt for Biarritz, but Gloucester struck a telling blow on the stroke of half-time.

Biarritz finally cracked under sustained pressure, with Tindall’s floated pass finding Simpson-Daniel who sprinted over unopposed – then added a celebratory dive – to give Gloucester a healthy advantage.

Barkley added the extras, giving Gloucester a 16-3 interval advantage and leaving Biarritz with the proverbial mountain to climb.

They struck first after the break though, slicing open Gloucester’s defence when centre Romain Cabannes made a slashing break that saw him send Gobelet over.

Peyrelongue converted, flashing warning signals in Gloucester’s direction that saw them respond through another Barkley penalty.

It was another nervy European night for Gloucester, who have displayed a worrying tendency to implode during Ryan’s coaching reign when the pressure comes on.

They bowed out of last season’s Heineken Cup at the quarter-final stage, beaten on home soil by Munster, then failed to reach the Guinness Premiership final despite finishing top after 22 games.

Biarritz, sensing they could push Gloucester to the limit, had no intention of switching off and contenting themselves with a losing bonus point.

The closing quarter proved a tense, error-strewn affair with Gloucester content to hold on and Biarritz searching desperately for a bonus that was denied them by a late Lamb strike.

And the muted response from an 11,700 crowd told its own story when Allen blew time on a game that fell way short of expectations.