Tonight's hotly anticipated fixture of the evening is none other than Atletico Madrid v Bayern Munich. Two of the continent's finest will slug it out in the group stage this season, likely battling for first and second place, leaving little more than scraps for PSV Eindhoven and FC Rostov to feed off.
And the pair have a very recent history as well, after Atleti nudged Bayern out of the competition on away goals at the semi-final stage last season.
The result was, in part, influenced by one of the finest solo goals the competition has seen in recent years. Juan Bernat remembers - he had a great view, as it happens.
Xabi Alonso got an eyeful as well.
Robert Lewandowski denies it, but deep down he remembers.
Arturo? Don't be like this, Arturo.
Yes, it's time to relive that monumental goal again.
After running aimlessly with the ball, Saul Niguez changed up a gear and ran away from one tackle, before swerving in between two more.
With space to run into the penalty area, Niguez toyed with David Alaba before cutting onto his left foot, clipping the ball in off the post past Manuel Neuer.
The goal proved the winner in the first leg, and Diego Simeone's side went on to progress on away goals after a 2-1 loss at Bayern's Allianz Arena in the return fixture.
Bayern will have to try to forget this smiling face...
Put their disappointment behind them...
And go again. The gloves are off.