#3 Atletico Madrid's counter-attack threatens Chelsea
Despite staying behind the ball for the majority of 90 minutes, Atletico Madrid's quality on the diagonal threatened Chelsea's goal.
In the 58th minute, it only took a handful of passes for Angel Correa to find space and then set up Suarez. The Uruguayan's effort was blocked by Andreas Christensen, who mopped up every possible instance of danger with his shrewd positioning.
A few moments later, Joao Felix let fly a fine-tuned bicycle kick over the bar. They won corners and found space to run into with slicker, quicker exchanges in wider areas.
Felix, in particular, was creative, and it was surprising to see him subbed off when Atletico were chasing.
#4 Olivier Giroud breaks the deadlock with a worldie
Just when it seemed like the game would open up between Chelsea's sustained possession and Atletico Madrid's counter-attacking football, Olivier Giroud pulled a rabbit out of the hat to score a world-class bicycle kick.
Once again, the striker proved why experience is key. Besides the four goals he netted earlier in the group stages, he found the back of the net in the last moment against Rennes. Today, he scored the decisive away goal.
It was a loose ball inside the box that looped in the air awkwardly. Giroud, known for his acrobatics, released the perfectly-timed kick over his head and found the corner, leaving Oblak with no chance whatsoever.
Chelsea gained advantage through a truly special moment and smartly saw Atleti out with disciplined defending.
#5 Decision-making the key for Chelsea ahead of second leg
The scoreline, statistics and the sheer number of chances created indicate an authoritative performance from Chelsea.
If one reads between the lines, however, the Blues could have and should have been more brutal in the final third. They outwitted Atletico with the quality and weight on the final ball, but it could have been better.
Kovacic and Mount often broke through the stacked midfield of their opponents and played it out wide. The likes of Alonso and Werner could have applied themselves better with the final ball.
It's that bit of decision-making, ruthlessness and decisiveness in the box that separates Chelsea from Europe's deadliest outfits. Of course, the players are bound to gradually understand Tuchel's system and improve under his stewardship.
But if they are to upstage a hungry Atletico Madrid side in the second leg, they will have to defend with the ball and take their chances instead of sitting back.