10 Dec, 12:23
Ireland's John Lacey will referee his first ever RBS 6 Nations match in February, while Alain Rolland is also included in the Elite Panel in what is his last season.
Gaffney's side need to overcome the Ospreys to reach the semi-finals. If they do so, Sarries will have home advantage against either Gloucester of Munster.
During his three-year tenure at Munster between 2002 and 2005, Gaffney guided the province to one quarter-final and two semi-finals in the Heineken Cup.
Meanwhile, first-time quarter-finalists London Irish will be at home to either Toulouse or Cardiff Blues in the first semi-final, provided they can see off the challenge of Perpignan in the last-eight.
The semi-finals will be played over the weekend of April 26-27.
2007/08 HEINEKEN CUP SEMI-FINAL DRAW:
London Irish or Perpignan v Toulouse or Cardiff Blues
Saracens or Ospreys v Gloucester or Munster
Meanwhile, the dates, kick-off times and host broadcasters for the 2007/08 Heineken Cup quarter-finals on April 5-6 have been confirmed. Additional TV details will be announced shortly.
2007/08 HEINEKEN CUP QUARTER-FINALS:
Saturday, April 5 -
London Irish v Perpignan, 3pm (local time) Sky Sports
Gloucester v Munster, 5.30pm (local time) Sky Sports
Sunday, April 6 -
Saracens v Ospreys, 12.30pm (local time) Sky Sports
Toulouse v Cardiff Blues, 4pm (local time) France Televisions