3 reasons why Leipzig toppled Champions League veterans Atletico

RB Leipzig reached the Champions League semifinals Thursday following a gripping 2-1 defeat of Atletico Madrid in Lisbon.

Dani Olmo and Tyler Adams netted a goal on either side of a Joao Felix penalty to extend Leipzig's first appearance in the tournament's knockout rounds. Now Julian Nagelsmann's outfit is potentially only 180 minutes away from hoisting the big-eared trophy.

Here are three reasons why the German upstarts overcame Diego Simeone's Atleti in the quarterfinals.

Leipzig's maturity

How RB Leipzig will cope with life after Timo Werner's sale to Chelsea was an inevitable talking point ahead of the match. Nagelsmann attempted to fill the gap by picking Yussuf Poulsen to lead his front line while putting more trust in other players to provide width and invention.

It all resulted in a more measured version of Leipzig's attack, rather than the unpredictability and darting runs that defined their upfield forays earlier in the competition.

There was a clue in the third minute to how Leipzig would approach the tie. The ball spilled to Marcel Sabitzer on the edge of the area, but rather than prod a forward pass to Olmo or try to lose his marker and carve out his own opportunity, he sensibly stabbed a spinning ball to left wing-back Angelino. Leipzig were prepared to work and wobble Atleti's stubborn defense like a baker kneading dough, relying on the attacking width initially offered by Angelino and Christopher Nkunku on the left and Konrad Laimer on the right.

When the game's opening goal finally arrived in the 50th minute, it was no surprise it followed a string of horizontal, methodical passes.

Leipzig already miss Werner's firepower - he's scored two more goals than Poulsen, Nkunku, Patrik Schick, and Emil Forsberg combined this season - but the team's understanding and maturity around the box meant that, on this occasion, the loss of his creativity wasn't obvious.

Contrasting fortunes for Atleti's attackers

One of the revelations of Atletico's season has been the emergence of Marcos Llorente as a viable attacking option.

Before this term, Llorente had made his name as a streetwise defensive midfielder, a player adept at thieving possession and then passing the ball onto a teammate who's likelier to instigate attacks. His work ethic in training and stamina in matches is, for the most part, unrivaled. He was a quintessential Simeone grappler.

But, through his remarkable two-goal cameo at Liverpool in the previous round, and his subsequent skillful and creative outings during La Liga's restart, Llorente was furnishing a reputation as a combative No. 10 in recent months.

Sadly, Thursday's match may prompt a revision of Llorente's role. At halftime, the Real Madrid product had the fewest touches (nine) and passes (six) on the pitch as he struggled to link the midfield with striker Diego Costa (who had the third-lowest number of touches in the first half with 15).

When Felix was called off the bench after 58 minutes, Llorente was much more effective while he wrestled at the edge of Atleti's narrow midfield. And Felix, of course, showed Llorente how to fulfill second-striker duties while he effortlessly received the ball between the lines, completed three take-ons, and earned and converted Los Colchoneros' equalizing penalty.

This probably isn't the end of Llorente's days as a battle-hardened attacker - after all, Simeone would love to field a team of defensive-minded players. But his deployment there should be more of a stop-gap solution or a Plan B for a club with ambitions of winning the Champions League crown.

The game could've been very different if Felix had played from the start.

Nagelsmann flourishes in one-off encounter

Simeone had success introducing Felix, but Nagelsmann won the skirmish between two very different tacticians. Atletico are one of the continent's most consistent clubs in two-legged affairs, having reached at least the quarterfinals in five of the past seven seasons, but Nagelsmann was able to take advantage of the unique one-match format.

The German coach hinted that Atleti's pedigree would be negated by the makeshift tournament's structure during Wednesday's press conference.

"We know that they have a lot of experience over two legs, but anything can happen in just one game," Nagelsmann said.

"We will all be thrown into cold water because of this situation, so experience isn't as big a factor as it might have been."

Atletico had the bigger names on the bench, including Felix, Thomas Partey, Alvaro Morata, and Thomas Lemar, but Nagelsmann - who is known for making several tweaks from the touchline - stayed true to his game plan. He simply brought on fresher legs rather than implementing radical tactical shifts. Adams, who scored the match-winner, was brought on in the 72nd minute in a like-for-like change for Laimer.

It was an impressive display of restraint by Leipzig's 33-year-old handler.

Losing Werner may have robbed Leipzig of some predictability in their attack, but the absence of their former talisman could also leave opponents guessing how they will approach the next two rounds. A Werner-less Leipzig is still a very new proposition.

That in itself could lead Nagelsmann's side to a shock Champions League triumph.

Leipzig face Paris Saint-Germain in the semifinals next Tuesday.