Cardiff Blues fought back from 24-7 down at the break against Pau to earn two bonus points and kept alive their slim Challenge Cup quarter-final hopes.

Tries for Mahamed Boughanmi, Geoffrey Moise, Pierre Nueno, Bastien Pourailly and Baptiste Pesenti seemed to have put Pau in control.

Owen Lane replied with a hat-trick while Hallam Amos also hit back as Blues produced a second-half fightback.

With two defeats from four European games, Blues still face an uphill task.

Leicester are unbeaten at the top of Pool 5 with two rounds to come with John Mulvihill's Blues a point behind them.

Bad weather had forced the postponement of the match, which was originally due to kick off at 20:00 GMT on Friday but rescheduled for 12:00 GMT on Saturday.

The local authority enforced the game's postponement on Friday night and with the game kicking off 16 hours later than planned in much better weather conditions, Blues actually started the better of the two sides with Wales wing Lane running in for the game's opening try.

Pau though dominated from then until the hour mark with their forward power causing the Welsh side major problems.

Boughami, Moise, Nueno and Pourailly crossed to give the French side a comfortable half-time lead with Presenti adding a fifth try after the break.

Replacement Amos responded with his first Blues try with Lane then crossing twice to bring the Blues within five points.

Clovis Le Bail and Jason Tovey exchanged late penalties meaning Blues head home with two bonus points in defeat and remain second in Pool 5 behind leaders Leicester.

Blues now travel to face Leicester and host winless Calvisano in their final two matches in January.

The Welsh region must win both remaining games and hope Leicester also slip up in Pau to have any hope of progressing in the competition.

Cardiff Blues coach John Mulvihill told BBC Sport Wales:

"They certainly won the first half and played some good rugby and didn't allow us out of our own half.

"But in the second half we were pretty close to faultless bar one or two little errors that probably cost us.

"To give a team like that in this competition such a head start is probably not the right thing to do and we gave away the first four penalties.

"We came out in the second half and basically blew them away and that's the sort of rugby we need to start playing."

Pau: Smith; Pourailly, Nueno, Septar, Fumat; Taylor, Daubagna; Moise, Lespiaucq Brettes, Boughanmi, Pesenti, Marchois, Erbani, Habel Kuffner, Whitelock

Replacements: Barka, Pointud, Fisiihoi, Metz, Puech, Le Bail, Debaes, Pinto.

Cardiff Blues: Morgan; Lane, Lee-Lo, B Thomas, Adams; J Evans, T Williams; Gill, Myhill, Andrews, Paulo, Turnbull, Lewis-Hughes, Robinson, Boyde (capt).

Replacements: Belcher, Domachowski, Assiratti, Ratti, Lawrence, L Williams, Tovey, Amos.

Referee: Tom Foley (England)

Assistants: Jack Makepeace (England), Jonathan Healy (England)