Debutant Pontus Wernbloom scored a stoppage-time equaliser to deny Real Madrid the victory from their trip to CSKA Moscow this evening.
The first chance of the match fell to the hosting Russians, but midfielder Alan Dzagoev was unable to get his volleyed effort on target from six yards out.
Madrid began to impose themselves on the tie following the opening exchanges and created their first chance in the 17th minute. Gonzalo Higuain, on for the injured Karim Benzema, saw his shot parried by Sergei Chepchugov. The goalkeeper then reacted quickly to turn Sami Khedira's rebound effort over the crossbar.
However, Chepchugov was unable to prevent Madrid from taking the lead in the 27th minute. Zoran Tosic failed to clear a cross from Fabio Coentrao and Ronaldo was on hand to send a left-footed effort beyond the reach of Chepchugov from 18 yards out.
Jose Callejon had two identical chances to extend Madrid's lead shortly after the break, but on one occasion he shot wide while on the other Chepchugov came off his line to block his low effort.
Moscow struggled to create goalscoring chances throughout the match, although 19-year-old winger Ahmed Musa did test Iker Casillas with powerful strike.
Ronaldo had two opportunities to make the game safe as time run out, but he shot wide both times.
His failure was punished in stoppage time when Wernbloom stole in to score from close range with just seconds remaining.
