The English Premiership's top two sides, Arsenal FC and Chelsea FC, meet in their quarter-final first leg at Stamford Bridge, while at the Santiago Bernabéu, Real Madrid CF will welcome AS Monaco FC.
London will, for the first time since 1961/62 produce a European Champion Clubs' Cup semi-finalist and form, at least, is on the side of Arsenal, who are unbeaten against Chelsea for six years and 16 matches - and have already beaten them three times this season.
The last time two English sides met in Europe's premier club competition was in 1978/79 when Nottingham Forest FC, that season's eventual winners, overcame holders Liverpool FC 2-0 on aggregate.
In Madrid, the Spanish champions face Didier Deschamps' Monaco hoping to put behind them a "black week" - the words of coach Carlos Queiroz - which brought defeats in the Spanish Cup final and the league.
Morientes heads home
Madrid's prospects are helped by the return of Ronaldo, and it should be an emotional occasion for Fernando Morientes, the Madrid striker who is spending this season on loan at Monaco. He has scored five goals in seven Champions League games already this term and is unlikely to let sentiment affect his scoring touch.
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