Real Madrid coach Zinedine Zidane opted for a switch in formation due to the number of injuries he had to deal with as Ferland Mendy, Sergio Ramos, and Fede Valverde were unavailable for the game. Tuchel continued to deploy Cesar Azpilicueta at right wing-back with Mason Mount, Timo Werner, and Christian Pulisic as the front three.
It was a thoroughly entertaining 90 minutes of football at the Alfredo Di Stefano stadium which got off to a flying start after Christian Pulisic blitzed past the Blancos' defence to score a brilliant goal in the opening 15 minutes. The American ran circles around Real Madrid's backline and beat Thibaut Courtois to slam the ball into the net.
Real Madrid then hit back via the brilliant Karim Benzema as the Frenchman turned up for the occasion with a brilliant volley from a short-corner routine. The goal sparked Zinedine Zidane's side back to life after a suspect first quarter of the game. Both sides adopted a bit more of a cautious approach once the weather got worse as it led to a number of slips, mistimed tackles, and misplaced passes from both sides.
In the end, although Chelsea have the added advantage of an away goal to their name, the tie remains well-poised and is set up for a blockbuster return leg in West London.
Here are some of the major talking points from the game.
#5 Chelsea could rue their first-half wastefulness
Chelsea began the game with a brilliant spell and were easily the more dominant side in the first 30 minutes. The likes of Pulisic and Mason Mount were too quick to handle for the hosts and they opened up the visitors on a handful of occasions. Naturally, this led to a fair few chances which they could have and should have put away.
Timo Werner was wasteful against Real Madrid, and failed to score what should have been an early opener for the Blues. Mount picked out a perfectly weighted cross to find Pulisic who then set up Werner with a lovely header. The German failed to convert from a few yards out. A minute later, Azpilicueta delivered another fantastic cross into the box and Werner failed to get to it by some distance.
As the game went on, Real Madrid regained some sense of control but the first half hour of the game was an uncharacteristically sluggish and sloppy display from the hosts, which Chelsea should have capitalised on even further. With some of Real Madrid's injured stars likely to return to fitness before next week, they could live to regret missing those chances.
#4 Marcelo's inverted role didn't help Real Madrid
Marcelo is no longer capable of covering the length of the pitch as he did a few years ago and this is one of the reasons for him losing his place to Ferland Mendy, who has covered the most distance in this season's UCL (102,703m). Mendy's absence was felt by the side as Marcelo stepped in for him on Tuesday, and didn't do a particularly great job.
When in possession, the Brazilian veteran tucked into midfield on a number of occasions, allowing Vinicius to drift into wide areas to try and get in behind Azpilicueta, like he did against Trent Alexander-Arnold. It was a failed experiment in both ways as Vinicius didn't get the better of the diligent Azpilicueta who was watchful of the Brazilian, while Marcelo was a passenger in the middle.
He failed to keep up with Chelsea's lightning-quick transitions and he was run over time and again. There was a moment in the second half when he fouled an onrushing Pulisic in Chelsea's half of the pitch as he knew he couldn't keep up with the winger's pace, which perfectly summed up his outing on the night.