Atletico Madrid will take a 2-1 lead into next week's Champions League quarter-final second leg away to Borussia Dortmund.
Placed on the 'right' side of the draw, both teams must regard this as a huge opportunity to reach the showpiece event at Wembley. Atleti have twice been downed in the final under Diego Simeone's tutelage, while one-time winners Dortmund have struggled to assert themselves in this competition since they were beaten finalists in 2013.
The signs were initially ominous for the visitors as an irresistible Atleti produced a superb first-half display and took a 2-0 lead, but a resilient second-half showing means BVB will feel it's all to play for going into the second leg.
Here are some of the things we learned from Wednesday night's game.
Edin Terzic certainly has a pragmatic streak in him, and he surely would've emphasised the need for Dortmund to tame Antoine Griezmann at the Estadio Metropolitano.
By stopping Griez, you shun Atleti.
Instead, the canny Frenchman walked all over the visitors in the first half, leading the charge as the hosts took a 2-0 lead. Griezmann's movement was far too slick for veteran Mats Hummels and Emre Can at the base of midfield, with Atleti accessing their talisman whenever they wanted.
He combined superbly with flying wing-back Samuel Lino throughout, teeing up the Brazilian's goal with a genius scoop to bypass Julian Ryerson. Griezmann's influence was reduced somewhat after the restart as Atleti dug in, but he should've recorded another assist for Lino from a perfectly directed set-piece.
Dortmund have been plagued by unpredictability and woeful inconsistency this season.
Just ten days ago, Terzic's side produced an outstanding defensive display to shut out Bayern