Heinken Cup: Cardiff Blues 36 Published on Monday 23 January 2012 00:43 Cardiff Blues booked their Heineken Cup quarter-final place - but not before Wales coach Warren Gatland was dealt another major pre-Six Nations injury scare. rop Gethin Jenkins went off six minutes before half-time nursing what appeared to be a knee problem. Gatland has already lost forwards Luke Charteris, Alun-Wyn Jones and Lloyd Burns from the tournament while fly-half Rhys Priestland and flanker Dan Lydiate both suffered injuries yesterday. Despite Jenkins" early exit, the Blues secured a last-eight berth - albeit away against Heineken Cup holders Leinster - thanks to wing Alex Cuthbert's try double, a Lloyd Williams touchdown and 21 points from full-back Leigh Halfpenny, including five penalties. Edinburgh's bonus point win against London Irish at Murrayfield, though, means the Blues qualify as best runners-up and not Pool 2 top dogs, travelling to Dublin rather than hosting Clermont Auvergne. Racing pushed them all the way, scoring tries through their former Exeter full-back Josh Matavesi and wing Sireli Bobo, with fly-half Jonathan Wisniewski kicking three penalties, centre Francois Steyn two and scrum-half Sebastien Descons a conversion and penalty. Racing struck first when Wisniewski landed a long-range penalty, but the Blues responded immediately when Williams charged down a Steyn clearance before gathering a kind bounce and touching down. Halfpenny converted, only for Wisniewski to kick his second penalty, then Halfpenny continued an early scoring burst with a penalty that made it 10-6. The visitors then sliced through the Blues" defence after Bobo's one-handed pass created space, and Descons sent Matavesi over. Although Wisniewski missed the conversion, he soon completed his penalty hat-trick before injury forced him off. Halfpenny's second successful penalty cut the gap to a point, but Racing were good value for their advantage until they gifted their opponents a second try through more sloppy defensive work. Halfpenny ghosted past Steyn, then Fabrice Estebanez missed an easy tackle on Cuthbert, who touched down despite not being called back by referee Andrew Small for a knock-on. Halfpenny rubbed salt into Racing's wounds by kicking the conversion attempt that opened up a 20-14 lead. Blues suffered a double blow when Bobo rounded off an impressive move for Racing's second try - converted by Descons - before a forlorn-looking Jenkins limped off. And the penalty-fest continued as Halfpenny and Steyn swapped kicks, ending a first 40 minutes that saw Racing pinch a 24-23 lead. The Blues took less than two minutes to go back in front, prospering when Imhoff was guilty of defensive hesitancy, and Cuthbert gathered before sprinting over in the corner. Halfpenny's conversion took the Blues up to 30 points, and it was a lead they managed to retain, even though their performance level looked well short of what will be required to challenge Leinster in early April. Halfpenny sealed the deal with a late strike.