The wait is finally over  the Champions League is back, and tonight (Tuesday, September 16, 2025), Europe’s biggest clubs kick off their league-phase journey in the revamped format. From Arsenal’s return to San Mamés to Mbappé’s first UCL night with Real Madrid, here’s your complete deep dive into tonight’s fixtures, tactical themes, and predictions.

Fixtures Tonight – Champions League Matchday 1

Athletic Club vs Arsenal – 18:45 BST | San Mamés, Bilbao

PSV Eindhoven vs Union Saint-Gilloise – 18:45 BST

Benfica vs Qarabag FK – 21:00 BST

Juventus vs Borussia Dortmund – 21:00 BST

Real Madrid vs Olympique Marseille – 21:00 BST | Santiago Bernabéu, Madrid

Tottenham Hotspur vs Villarreal – 20:00 BST | Tottenham Hotspur Stadium, London

Game Previews & Key Talking Points

 

Athletic Club vs Arsenal

Arsenal begin their UCL campaign away to a passionate San Mamés crowd. However, they’ll be without Bukayo Saka and captain Martin Ødegaard, both sidelined by injury.

Arsenal’s Advantage: Depth in midfield (Declan Rice, Zubimendi, Moreno) and Gyokeres up front.

Athletic Club’s Edge: Noise, pressure, and intensity of their home crowd, marking their long-awaited UCL return.

Prediction: Arsenal slight favourites, but a draw wouldn’t shock.

PSV Eindhoven vs Union Saint-Gilloise

Union SG make their Champions League debut. PSV are heavy favourites at home, boasting experience and attacking flair. But Union SG’s Cinderella rise in Belgian football means they’ll bring fearless energy.

Prediction: PSV to control, but Union SG could surprise.

Benfica vs Qarabag FK

Benfica rarely slip at home. They’re unbeaten in recent matches and boast a solid defensive core alongside creative attackers like Rafa Silva. Qarabag, usually cautious on the road, will likely defend deep and counter.

Prediction: Benfica comfortable winners.

Juventus vs Borussia Dortmund

This is the heavyweight clash of the night.

Juventus: Fresh from a wild 4-3 win over Inter, showing both attacking flair and defensive fragility.

Dortmund: Still inconsistent defensively, but dangerous with Adeyemi, Malen, and Brandt.

Prediction: Goals are expected — over 2.5 goals very likely.

Real Madrid vs Olympique Marseille

Madrid begin their campaign under the brightest spotlight Kylian Mbappé’s UCL debut in white.

Madrid’s Focus: Dominating possession, with Gular and Vinícius feeding Mbappé.

Marseille’s Challenge: Away form has been shaky; frustrating Madrid early will be key.

Prediction: Madrid favourites to win, but Marseille could make it nervy.

Tottenham Hotspur vs Villarreal

Spurs return to Champions League football.

Spurs: Richarlison expected to lead the line, new signing Kudus could finally get a Champions league feel.

Villarreal: Will look to disrupt rhythm and hit on quick counters.

Prediction: Spurs narrow win, but expect tactical tension.

Tactical Themes

High Pressing vs Deep Blocks: Arsenal, Real Madrid, and Juve will push forward; expect their opponents to counterpunch.

Big Names Under Pressure: Mbappé, Gyokeres, Iniaki Williams, and Eze must step up as leaders.

Debuts & Drama: Union SG’s first UCL night, Athletic Club’s emotional homecoming, and Madrid’s galáctico project all fuel tonight’s drama.

Why Tonight Matter

The new league-phase format makes early points even more valuable. Wins now reduce pressure later. Goal difference isn’t everything, but momentum and psychological edge count for plenty.