The games in Manchester and Leverkusen were high-scoring affairs
Tuesday's Champions League games saw wins for Manchester City and Atletico Madrid in two outstanding matches.
Manchester City overcame a 3-2 deficit, to score three goals in the last 20 minutes to win 5-3. In Germany, Atletico Madrid defeated Bayer Leverkusen 4-2.
The 14 goals scored in both games, means that a single day of Champions League football has finally broken the seven goal barrier.
Three matchdays (including two finals) had seen a six goal average, but the second night of 2003 Champions League quarter-final second-legs is the only time a six-goal average has been seen over more than one game.
Manchester United defeated Real Madrid, 4-3 in Old Trafford, while AC Milan were 3-2 winners over Ajax, courtesy of an injury-time winner from Jon Dahl Tomasson.
The game in Old Trafford is best remembered for Ronaldo's hat-trick. The Brazilian striker was given a standing ovation from the crowd when he was substituted.
Wednesday's games in Seville and Porto have a lot to live up to.