Paul Burke will be thrust into the Heineken Cup quarter-final spotlight in the wake of Ronan O'Gara - the tournament's leading points scorer - suffering a serious knee ligament injury in the 24-8 Celtic League victory over Newport Gwent Dragons at the weekend.
Burke came on as replacement fly half to land all three conversions and is set to be called up to start at No 10 against Biarritz Olympique at Estadio Anoeta in San Sebastian on Sunday afternoon.
Both Irish teams through to the quarter-finals warmed up with domestic wins, Leinster beating Llanelli Scarlets 31-25 at Lansdowne Road where they will tackle Leicester Tigers on Saturday.
But the Tigers slipped to a 23-22 defeat against Leeds Tykes at Headingley - their fourth defeat on the trot at the ground - to have their lead at the top of the Zurich Premiership cut to four points.
And Newcastle Falcons, who travel to the French capital to face Stade Francais Paris on Saturday as the only "newcomers" to the knock-out stages of the Heineken Cup, saw their nine-match unbeaten home run halted when they went down 9-5 to Bath Rugby as well as seeing three of their props, including joint club captain Ian Peel, forced off with injuries.
Director of Rugby Rob Andrew declared: "We have to pick ourselves up if we are to prove we are good enough to reach the semi-finals of the Heineken Cup."
Northampton Saints snatched victory from the jaws of defeat with a Mark Tucker injury time try converted by Shane Drahm in their 22-20 win over NEC Harlequins while in the French Top 16 home advantage was the key.
And Toulouse must have had the Saints alarm bells ringing as their 10 tries against Brive saw them record a thumping 71-3 victory, the second biggest winning margin in a Top 16 game this season.
Clement Poitrenaud and Cedric Heymans each crossed twice and Jean-Baptiste Elissalde and Frederic Michalak cashed in with the boot ahead of the Saints trip to Le Stadium in Toulouse for the first quarter-final on Friday night.
However, it was not such good news for Stade Francais Paris as they suffered their heaviest defeat of the season at the hands of fellow quarter-finalists Biarritz.
Dimitri Yachvilli kicked six out of six and tries from Imanol Harinordoquy, Philippe Bidabe and two from Nicolas Brusque meant Biarritz came away with five points from the fixture to boost morale ahead of the Munster showdown.
Stephane Glas, the Stade Francais centre, said: "We were going sideways. It's worrying before the Heineken Cup quarter-final against Newcastle."
