Chelsea will leave the Spanish capital with a slight advantage after playing to a 1-1 draw against Real Madrid in the first leg of their UEFA Champions League semi-final.
Los Blancos made three changes from the side that drew with Real Betis, as Marcelo, Toni Kroos and Vinicius Junior returned while the Blues were unchanged from the side that beat West Ham United.
The Blues had a bright start as the attacking trio combined to great effect in the tenth minute, with Mount supplying a cross that was put on the plate for Werner, who saw his half-volley saved by goalkeeper Thibaut Courtois.
Pulisic eventually opened the scoring for Chelsea four minutes later after latching onto a long ball over the top by Antonio Rudig before rounding Courtois to fire an empty net.
Karim Benzema came close to finding the equaliser for Madrid in the 23rd minute with a strike that came off the post after running at the Chelsea defence.
The Frenchman was not to be denied five minutes later with an acrobatic volley from close range after cushioning Eder Militao's flick on with a header to level matters on the night.
The game was still open after the break, with Zinedine Zidane's charges a constant threat while the English side were looking for chances on the break using Werner's speed.
However, in the same moment as Madrid brought on Eden Hazard against his former side in place of Vinicius Junior in the 66th minute, Tuchel altered his tactics with a triple change after bringin on Hakim Ziyech, Kai Havertz and Reece.
Los Blancos put the pressure on Chelsea but they were unable to find spaces in the last third, which prompted Zidane to throw on Marco Asensio and Alvaro Odriozola in the final 13 minutes.
Kroos had a chance to snatch the winner for the hosts with a deflected strike from the edge of the box that missed wide but 1-1 was the first leg ended, with the Blues having the advantage of an away goal heading into the second-leg next Wednesday at Stamford Bridge.
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