Originally a straight knockout competition open only to champion clubs, the tournament was expanded during the 1990s to incorporate a round-robin group phase and more teams.
With 140 goals, Cristiano Ronaldo is currently the all-time top scorer in the Champions League, with Lionel Messi and Robert Lewandowski being the only other players to have reached triple figures.
Ronaldo has also finished as the top scorer for the most individual seasons in the competition's history, doing so seven times.
The title of highest goalscorer had previously been held by Raúl, who scored his 50th goal in 2005 while at Real Madrid to overtake Alfredo Di Stéfano.
[4][5] Ronaldo has remained the competition's outright top scorer since September 2015; after a back-and-forth exchange of the record between him and Messi, a hat-trick by the former against Shakhtar Donetsk put Ronaldo ahead with 80 goals, and he would not relinquish the top spot again after this.