Champions League semi-finals: Breaking down where RB Leipzig vs PSG and Lyon vs Bayern Munich will be won and lost

Tactics, ideologies and individual brilliance will all be on display as the final four teams chase the two spots in Sunday’s final

Screengrab of PSG playing Atalanta in the Champions League (BT Sport)

The semi-finals of the Champions League get under way on Tuesday evening as RB Leipzig take on Paris Saint-Germain.

Then, on Wednesday, it’s another French vs German clash as underdogs Lyon face the only team left in the tournament to have previously won it: Bayern Munich.

Tactics, ideologies and individual brilliance could all be factors in determining which sides get through to Sunday’s final. And – as with the quarter-finals – the new dynamic of these ties consisting of just a single leg could affect proceedings.

Here is a look at where the semi-finals of this year’s Champions League will be won and lost.

RB Leipzig vs PSG (Tuesday 18 August)

A raft of injuries forced Thomas Tuchel into a tactical re-jig for last Wednesday’s dramatic Champions League quarter-final against Atalanta. With Kylian Mbappe only fit enough to make the bench and Angel Di Maria and Marco Verratti’s creativity also missing, the German coach opted for a 4-3-3 with a twist.

During PSG’s last competitive fixture in the Coupe de la Ligue final against Lyon (which Mbappe was also missing for), he had played a conventional 4-3-3 with Mauro Icardi through the middle and Neymar to the left. This time, he made the conscious decision to harness Neymar’s creative powers in central zones as a false nine, flanked by Icardi in an unfamiliar right-wing role and Pablo Sarabia on the left.

Neymar was brilliant throughout, completing a staggering 15 dribbles and creating 5 chances during the match. The tactical role gave him the licence to roam into deeper areas and his favoured inside left channel. When Mbappe and Eric Maxim Choupo-Moting entered the fray on the flanks, we saw Tuchel’s decision pay dividends. Both players stretched Atalanta’s defence with runs in behind, which Neymar would find with his delicate weight of pass or use as a decoy to dribble past his marker. With Mbappe and Di Maria fit to start out wide against Leipzig, Tuchel will undoubtedly consider employing the same Neymar false-nine tactic to replicate PSG’s improved performance in the last 30 minutes against Atalanta.

Neymar and Kylian Mbappe are key to PSG’s successful forward moves (Build Lineup)

Similarly, Tuchel’s fellow German coach Julian Nagelsmann selected one of his standard formations (3-4-3) in the quarter-finals, but also with an element of surprise. This was mainly surrounding the role of his Austrian lieutenant Konrad Laimer. When Leipzig were in possession, Laimer offered width as a right wing-back, but then off the ball Laimer would shift inside alongside Kevin Kampl in midfield, with Lucas Klostermann moving across from the right side of a back three to his natural right-back position.

This morphed Leipzig’s formation from a 3-4-3 into a 4-2-3-1 to provide more defensive stability in central areas. Nagelsmann may see it appropriate to implement this dual system against PSG, particularly with the aforementioned threat of Neymar roaming centrally. Neymar’s chemistry with Mbappe down the left was clear to see in the last round, with the Brazilian finding his runs in behind several times, including for the Choupo-Moting winner. Therefore, Laimer could have a crucial role to play, stopping attacks down that side.

One area where PSG will certainly have to improve is their pressing from the front. Too often they allowed Atalanta’s back three to step out with the ball and build attacks. They cannot afford to fall down the same trap against Leipzig – Dayot Upamecano’s ball-carrying from the back was a key reason why the German side could breach Atletico Madrid’s compact 4-4-2 shape so regularly. There was one particular occasion where Upamecano picked up the ball in his own half, bypassed Llorente’s press, then entered midfield, dribbled past Saul and then finished off by releasing Laimer down the right wing. This is another factor that makes Mbappe and Di Maria’s selections instead of Sarabia and Icardi more likely.

Dayot Upamecano’s ball-carrying ability was on display against Atletico Madrid (Build Lineup)

It will be interesting to observe how Leipzig cope in the final third without Timo Werner. Against Atletico, target man Yussuf Poulsen started up front and his role was to trap direct balls into him – either aerially or from the likes of Upamecano and Kampl along the ground – and link with one of three attacking midfielders (Christopher Nkunku, Dani Olmo and Marcel Sabitzer), finding spaces in between the lines that Nagelsmann said he had consciously selected. Patrik Schick then joined in with this ploy as a second target man after 83 minutes.

Atalanta did this to varying degrees of success against PSG, with Duvan Zapata often holding the ball up in wide channels and pulling PSG’s centre-backs with him. But then with Josip Ilicic missing and Luis Muriel on the bench, they lacked someone to run in behind. Leipzig have no such concerns, with ex-PSG academy graduate Nkunku’s pace lining up in their attack. His link with Poulsen and/or Schick could be vital in determining the outcome of this tie.

Lyon vs Bayern Munich (Wednesday 19 August)

Bayern’s extremely high press in their quarter-final versus Barcelona was a huge contributor to their comprehensive 8-2 victory – particularly in the first 31 minutes, when Bayern raced into a 4-1 lead. In total, Bayern’s starting front six made 19 ball recoveries in the middle and attacking thirds. Barca’s front six made just six.

Lyon must ensure they aren’t caught in this Bayern whirlwind by not overplaying at the back. And in fairness, after Man City’s press had looked fine-tuned against Real Madrid after forcing Raphael Varane into two pivotal errors, Lyon evaded any similar damage and their back five were not dispossessed by a Man City player during the entire 90 minutes. They achieved this by primarily playing long in their build-up. Twenty-one percent of Lyon’s passes during the game were long balls. Against Juventus, this figure was only at 16 percent in both legs. There was a concerted effort to avoid the perils of Man City’s press. Expect a similar approach against Bayern.

Bayern’s intense press does also come with a pay-off. In order to compact the space in the middle of the pitch, Bayern’s midfield (Thiago and Leon Goretzka) push up behind their forwards and in turn so do their defensive line. Consequently, Bayern maintain a very high defensive line. In most situations, they manage this well with the pace of Alphonso Davies and David Alaba particularly useful. However, there were occasions where Barcelona were able to breach their high line and this was without playing a pacey forward like Ansu Fati or Ousmane Dembele.

Lyon, meanwhile, have the express speed of Maxwel Cornet at left wing-back and Karl Toko Ekambi to call upon. Guardiola explicitly played three centre-backs to cover for long balls into the wide channels to Lyon’s quick players, yet the French side still managed to succeed with this tactic. In the build-up to the first goal, it was Fernando Marcal’s brilliant pass to Toko Ekambi that penetrated Man City’s high line down their right side. Lyon may seek similar success down Bayern’s right side, with Joshua Kimmich and Jerome Boateng not as quick as Davies and Alaba on the left.

Lyon’s back five is protected by a narrow but very energetic midfield three of Maxence Caqueret, Bruno Guimaraes and Houssem Aouar. Consequently, Lyon become very tough to penetrate through the middle of the pitch, happily surrendering space out wide. Juventus and Man City both found this to be the case. Instead of Thiago’s line-breaking passes through the middle, the flanks may be Bayern’s best avenue to create chances.

This, in part, led to a Lyon deficiency that Man City were able to expose. Often when City were able to build play out wide, a chasm of space appeared between Lyon’s right wing-back (first Leo Dubois then Kenny Tete) and Jason Denayer (their right-sided centre-back). They repeatedly found Raheem Sterling’s darting underlaps into this space, including the assist for Kevin De Bruyne’s equaliser. Thus, Dubois was taken out of the firing line for Tete on 74 minutes. With Davies capable of accelerating into similar spaces from deep and Ivan Perisic and Thomas Muller’s intelligent movement that can exploit such spaces, Lyon must defend this area of the pitch much more proficiently against Bayern.