Nine goals in Paris, two penalties in Madrid: What the UCL semi-final first legs told us about each tie

Two Champions League semi-final first legs in 24 hours. Nine goals in Paris on Tuesday, two penalties and VAR controversies in Madrid on Wednesday. PSG lead Bayern 5-4 and Atletico and Arsenal drew 1-1. Both ties are alive, but the character of the two evenings could not have been more different, and the tactical story behind each scoreline is something you should understand properly.

Paris Saint-Germain 5-4 Bayern Munich

Luis Enrique set up PSG in their familiar shape, a high defensive line, aggressive pressing from the front, Kvaratskhelia and Dembele wide with license to cut inside, and Joao Neves dictating the tempo from central midfield. Kompany mirrored them with his own high line, Kimmich and Pavlovic holding behind Musiala and Olise, Kane as the focal point. Both managers essentially decided to play the same game: press high, win the ball fast, attack at pace, and trust their forwards to make the difference.

Neither of them asked their side to defend deep. Neither of them prioritised keeping a clean sheet. The result was the highest-scoring semi-final in Champions League history.

Kane's penalty opened the scoring after Hakimi's handball, VAR confirming the spot-kick. PSG's response said everything about how Enrique's side process don't slow down, they don't reorganise cautiously, and they press harder. Kvaratskhelia equalised with a low finish, Joao Neves put them ahead, then Dembele converted a penalty for the handball given against Davies to make it 3-1 at the interval.

The first-half scoreline told only part of the story. Per Flashscore, Bayern created 1.53 expected goals before the break but could only convert Kane's spot-kick. Their high line, which had been effective all season in the Bundesliga, gave Kvaratskhelia and Dembele the space they needed behind the backline on both goals.

The second half weakened, tactically, into something like a basketball game. Kvaratskhelia scored his second, cutting in from the left after Hakimi's low cross found him at the near post. Dembele added a fifth three minutes later, finding the net via the inside of the post after a direct counter-attack that caught Upamecano and Tah completely flat. At 5-2 and an hour played, Bayern had a decision to make.

Aaron Danks, standing in for suspended Vincent Kompany, brought on Laimer for Davies at half-time to shore up the left side; it hadn't worked. He then sent on Goretzka and Jackson in the second half, making the team more physically direct, accepting the space it gave PSG at the back. Upamecano's header from Kimmich's free-kick made it 5-3. Luis Diaz, taking Kane's sublime long ball on his chest, cut inside and fired in for 5-4.

Both teams' backlines were vulnerable to balls in behind, both sets of forwards were clinical enough to punish that vulnerability many times, and neither manager showed any real desire to change the structure that was causing the problem.

Bayern Munich kept the high line even after conceding four. Enrique kept the aggressive shape even when the German team began pulling it back. Both teams' expected goals were actually lower than the goals they scored, which means both attacks were finishing above their xG.

What both sides showed is that their defence, while not what they're known by, makes them vulnerable at this level. The second leg in Munich next week sets up as potentially another nine-goal evening, or a very different game if either manager makes structural adjustments.

Kompany almost certainly has to.

Atletico Madrid 1-1 Arsenal

In Madrid, Simeone chose a 4-4-2 with Griezmann and Alvarez as the front two, Koke and Cardoso in central midfield, and the intention of sitting slightly off Arsenal and letting them have the ball in their own half before pressing intensely in the middle third. Arteta responded with a 4-3-3 in possession, Rice and Zubimendi as the double pivot, Odegaard between the lines, and Saka and Martinelli wide.

What both coaches built was a game of fine margins, where the first goal was always going to matter.

The first half was controlled, tense and low on clear chances. Alvarez tested Raya from distance and the Spanish goalkeeper did well to keep them out. Arsenal had the better of possession without doing much with it, Madueke's early cross to the far post came to nothing.

Then, in the 44th minute, Hancko fouled Gyokeres in the box and the tie changed. Gyokeres blasted the penalty low to Oblak's right. Arsenal went into the interval 1-0 up.

At the second half, the Metropolitano crowd got behind the home side, Griezmann began dropping deeper and collecting between the lines to combine with Alvarez, and Arsenal suddenly couldn't get out of their own half. A Marcos Llorente volley struck Ben White's arm in the box in the 57th minute. VAR confirmed the handball. Alvarez smashed his penalty into the top-left corner, giving Raya no chance.

Griezmann hit the crossbar with a falling volley at 1-1, one of the moments of the night. The game's decisive controversy came in the 78th minute: referee Danny Makkelie pointed to the spot when Hancko caught Eze, then spent three minutes at the monitor before overturning the decision.

Arteta was furious on the touchline. Simeone's reaction was the controlled celebration of a man who felt the universe had corrected itself.

Arteta's tactical read of the tie across the 90 minutes was largely sound. Declan Rice completed 83 passes, the second-most by an English midfielder in a Champions League semi-final on record, and made 12 line-breaking passes, the most of any player on the pitch. The double pivot of Rice and Zubimendi controlled the first half.

What Arsenal couldn't manage was sustaining that control once Simeone turned the volume up after the break. The second-half press that Atletico ran stretched Arsenal's back four in ways they hadn't faced in the first half, and the Griezmann crossbar moment was how close Atletico came to leading with five minutes still to play. The overturned penalty leaves the question of what Arteta's side would have done with a 2-1 lead and ten minutes to hold it genuinely unanswered.

From the two nights, we saw a PSG and Bayern side that both believe in expansive, high-risk, high-reward structures. Neither is built for a grinding 1-0. Both paid for that on Tuesday, and both will score goals in Munich next week.

Atletico and Arsenal, on the other hand, played a game that was physically demanding, tactically considered and settled by penalty kicks and individual moments rather than sustained attacking football. Neither side created enough from open play to win the match without the spot-kick decisions going their way. Both finals spots are still open. The next week is going to be excellent.