Pool A
Newcastle Falcons v Newport Gwent Dragons
At Kingston Park, Saturday 5.30pm. Live on S4C
Newcastle Falcons are in joint top spot in EDF Energy Cup pool A with Gloucester in this closest of all groups which produced two drawn games last weekend. The Falcons are unbeaten in their last three EDF Energy Cup matches since losing 5-28 at Sale in September 2006.
Newport Gwent Dragons are undefeated since Munster beat them 26-16 in the Magners League at Rodney Parade on 28 September. The Dragons have never won an away game in the EDF Energy Cup.
The two sides have met on two previous occasions in the 2004-05 European Cup with Newcastle winning both encounters: 10-6 at Rodney Parade and 25-17 at Kingston Park.

London Wasps v Gloucester Rugby
At Adams Park, Sunday 3pm
Since winning last season's European Cup London Wasps have won just one of their seven matches: 28-14 over London Irish in the Guinness Premiership on 14 October. Wasps have won all three previous home matches they have played at Adams Park in the EDF Energy Cup.
Gloucester Rugby are unbeaten in their last three encounters in the EDF Energy Cup since losing 19-49 at Ospreys in September 2006.
Wasps have won five of the last six games they have played against Gloucester, with Gloucester's only success in that time being a 27-21 at Kingsholm last season in the Premiership. Gloucester have never won in six previous visits to Adams Park in all competitions. 

POOL B
Sale Sharks v Bath Rugby
At Edgeley Park, Friday 7.45pm
Sale Sharks have won their last four matches at Edgeley Park in all competitions. The Sharks' last win in the EDF Energy Cup was 21-5 at home to Llanelli Scarlets on 2 December 2006.
Bath Rugby have won five successive games in all competitions, and have also won four of their last five encounters away from home.
Sale and Bath have already locked horns this season in the Guinness Premiership, with Bath victorious 21-19 at the Rec on 29 September.

Leicester Tigers v Cardiff Blues
At Welford Road, Saturday 2.30pm. Live on BBC Network
Leicester Tigers, last season's EDF Energy Cup winners, face elimination from this season's competition if they lose this match. The Tigers' have won all three previous matches they have played at Welford Road in this competition, whilst the last Welsh side to beat Leicester at Welford Road was Swansea on 20 November 1998.
Cardiff Blues have won seven of their last eight matches in all competitions and have not lost a pool game in this competition since a 23-27 reversal at London Irish on 4 December 2005.
The two sides met twice last season in the European Cup with the Tigers winning both matches: 21-17 at Millennium Stadium and 34-0 at Welford Road.

POOL C
Harlequins v Worcester Warriors
At Twickenham Stoop, Saturday 3pm
Harlequins have won ten of their last eleven matches at Twickenham Stoop in 2007, whilst their 10-8 win at London Irish on Sunday was their first ever win in the EDF Energy Cup.
Worcester Warriors have lost their last five matches in all competitions and have not won since beating Saracens in the Premiership on 28 April. The Warriors' last away win was at Sale on 9 March.
The two sides have met on four previous occasions: twice in season 2004-05 which were both won by Worcester, and twice last season which were both won by Harlequins. 

Ospreys v London Irish
At Liberty Stadium, Sunday 4.10pm. Live on S4C
Ospreys have lost just once in any competition at Liberty Stadium since May 2006: 9-14 to Llanelli Scarlets in the Magners League on 11 September 2007. Ospreys only defeat in their last seven encounters in the EDF Energy Cup was in last season's final at Twickenham.
London Irish have not won a game in the EDF Energy Cup since a 36-24 victory at home to Saracens on 30 September 2006, whilst their last away win in any competition was 12-7 at Bristol in the Premiership on 10 March 2007.
The two sides have not met before in a competitive match.

POOL D
Llanelli Scarlets v Leeds Carnegie
At Stradey Park, Friday 7.10pm. Live on BBC Wales
Llanelli Scarlets have only lost twice at Stradey Park in any competition since January 2006. The Llanelli Scarlets region have only ever suffered one defeat in competition matches against English opposition at the famous old ground: 20-22 to Northampton in the European Cup in January 2005.
Leeds Carnegie have won only one game so far this season: 26-21 over Worcester in the Guinness Premiership on 12 October. Leeds are yet to win in four previous matches in this competition.
Current Scarlets coach Phil Davies was of course head coach at Leeds for 302 matches for exactly a decade between 1996-2006, and was in charge at Leeds on the only previous occasion that the two teams have met: a 28-7 win for the Scarlets at Headingley Carnegie in this competition in October 2005.

Saracens v Bristol Rugby
At Vicarage Road, Sunday 3pm
The match of the round in the EDF Energy Cup pits together the top two sides in the Pool D table. Saracens' only loss in their last five outings was 30-34 at Sale in the Premiership two weeks ago. Likewise, Bristol Rugby have also lost just once in their last five encounters: 18-24 at Harlequins on 6 October.
Bristol have won twice in seven previous visits to Vicarage Road in all competitions: 28-26 in May 2002 and 19-13 in February 2006.