Chelsea host Inter Milan at Stamford Bridge on Tuesday night aiming to claw back a 2-1 deficit from the first leg at the San Siro.
Here Press Association Sport looks at the crucial encounters which could unfold on the pitch.
ESTEBAN CAMBIASSO v NICOLAS ANELKA
Argentina international Cambiasso will be charged with breaking up Chelsea's attacks. The defensive midfielder is deployed in the holding role that coach Jose Mourinho favours but proved in the opening leg that he can also deliver a devastating shot. Anelka is more than likely to find himself playing just behind main striker Didier Drogba and that will put him up against the combative Cambiasso. Anelka has enjoyed a superb season so far for the Blues but the France international will have to be at his very best to win this personal duel.
SULLEY MUNTARI v FRANK LAMPARD
Former Portsmouth midfielder Sulley Muntari is likely to have the unenviable task of preventing Lampard from winning the midfield battle. Mourinho tried to sign Lampard from Chelsea when he left Stamford Bridge but having failed in his attempt to lure the Englishman away for his former club, the 'Special One' went for next best thing - Portsmouth's Muntari. The pair have not always seen eye to eye at Inter, but Mourinho certainly rates him as a player. Hard-running, with flair to match his engine, Muntari will provide Lampard with a stiff test.
SAMUEL ETO'O v JOHN TERRY
Cameroon international Eto'o will provide the Chelsea captain with a real test - much as he did in the opening leg. Terry, at fault for both goals in the 2-1 defeat against Everton in the Barclays Premier League last month will have to be back to his very best to cope with 29-year-old.
