Gloucester's European Challenge Cup campaign began with defeat to Pau in France.
The Cherry and Whites, bidding to lift the trophy for a third time and go one better than last season's final defeat to Stade Francais, were beaten 27-21 in the Pool 3 opener.
The visitors paid for lapses of concentration in the first half and, just as they were threatening a comeback, another mistake proved costly as Frank Halai sealed Pau's victory.
The first score of this year's competition arrived in the 17th minute from Daniel Ramsay, who intercepted a wayward pass and slid over in the corner.
The hosts moved 14-0 ahead eight minutes later when Benson Stanley slipped in Colin Slade to race through and score under the posts.
Slade increased the lead after half-time with a couple of penalties to take his personal tally to 15 points.
Gloucester finally troubled the scorers in the 55th minute with Ruan Ackermann finishing a powerful maul, and - with 11 minutes left - the deficit was cut to six after Ben Vellacott went over and Owen Williams converted.
But moments later a loose Williams crossfield kick fell straight into the arms of Halai, who raced 80 yards to touch down.
That score ended Gloucester's hopes of victory but Henry Purdy did grab a late try and Williams converted for a losing bonus point.