Last season\'s Heineken Cup runners-up Northampton lost 28-23 at home to Llanelli on Friday, their second successive defeat in this year\'s competition.The English side, whose coach Jim Mallinder has been linked with the vacant England job, produced an error-strewn performance to sink to third in Pool One, seven points adrift of their opponents.    Munster are second behind Llanelli after Ireland flyhalf Ronan O\'Gara\'s drop goal in overtime secured a dramatic 27-24 win over Castres.Edinburgh top Pool Two after an astonishing late rally to beat Racing Metro 48-47, the Scottish side fighting back from 24 points down to steal an unlikely victory.Cardiff Blues also registered their second win with a 24-18 victory over London Irish and the Welsh team are just a point behind Edinburgh at the top.Defending champions Leinster overpowered Glasgow 38-13 and they lead Pool Three, two points ahead of Bath who edged out Montpellier 16-13 on Sunday thanks to an assured performance by New Zealand flyhalf Stephen Donald.Leicester saw off Ulster 20-9 on Saturday to take control of Pool Four, two points ahead of Clermont Auvergne who crushed Aironi 54-3.Biarritz, inspired by France forward Imanol Harinordoquy, notched up their first win with a 15-10 victory over Saracens who are level on points with Pool Five leaders Ospreys after the Welsh team were held to a 26-26 draw by Treviso.Surprise English Premiership leaders Harlequins claimed their second successive win with an impressive 28-9 victory at Gloucester and they are level with Pool Six leaders Toulouse who won 36-10 at Irish newcomers Connacht.