Title holders Real Madrid defeated 10-man Chelsea 2-0 to draw first blood in their Champions League quarter-final tie on Wednesday, while AC Milan won a first all-Italian date with 10-man Napoli 1-0.
Karim Benzema was on target for Real in the 21st minute at the Bernabeu and substitute Marco Asensio got the second in the 74th, after Chelsea's Ben Chilwell was sent off on the hour for a last-man foul on Rodri.
But 14-time champion Real still have work ahead of them on Tuesday at Stamford Bridge where the Blues and their interim coach Frank Lampard have a chance to turn matters around.
Milan beat Napoli again, 10 days after a stunning 4-0 Serie A triumph against the runaway leaders, with Ismael Bennacer's 40th minute strike making the difference at the San Siro where Napoli's Andre-Franck Zambo-Anguissa got his marching orders.
The seven-time champions need to complete the job in Naples in their quest to ultimately reach the final on June 10 in the Istanbul stadium where they lost the memorable 2005 decider on penalties against Liverpool after leading 3-0 at half-time.
Also keen for an Istanbul return will be Real coach Carlo Ancelotti, who was in charge at Milan in 2005, and celebrates his 64th birthday on the day of the this year's final.
The other first leg games were on Tuesday, with Manchester City downing Bayern Munich 3-0 and Inter Milan winning 2-0 at Benfica.
