UEFA Europa League – Semi-finals (First Leg)

2 May 2013

Chelsea – Basel

Referee: Jonas Eriksson (SWE, photo)
Assistant Referee 1: Mathias Klasenius (SWE)
Assistant Referee 2: Daniel Warnmark (SWE)
Additional AR 1: Stefan Johannesson (SWE)
Additional AR 2: Markus Strombergsson (SWE)
Fourth Official: Stefan Wittberg (SWE)
Referee Observer: Nuno Castro (POR)

Benfica – Fenerbahce

Referee: Stephane Lannoy (FRA)
Assistant Referee 1: Frederic Cano (FRA)
Assistant Referee 2: Michael Annonier (FRA)
Additional AR 1: Antony Gautier (FRA)
Additional AR 2: Ruddy Buquet (FRA)
Fourth Official: Laurent Stien (FRA)
Referee Observer: Manuel Lopez (ESP)