MADRID – Real Madrid punished two costly Inter Milan mistakes to win their Champions League opener 2-1 on Tuesday, with Kylian Mbappe and Federico Valverde scoring and goalkeeper Thibaut Courtois keeping the visitors at bay at the Santiago Bernabeu.

Erling Haaland struck twice after halftime as Manchester City won 2-0 at Porto, extending ​coach Enzo Maresca's winning start following three successive Premier League victories.

Real Betis twice came from behind to beat Lille 3-2 in France, with defender Marc ‌Bartra scoring twice before Troy Parrott grabbed the winner. Lille later had Ethan Mbappe sent off.

Serhou Guirassy's late double secured Borussia Dortmund a 3-2 home victory over Villarreal after the Spanish side had cancelled out Renato Veiga's own goal.

Earlier, Aston Villa held off Club Brugge to win 3-2 in Belgium, helped by two Pau Torres assists, while Razvan Marin's free kick earned AEK Athens a 1-0 home victory over LASK.

Courtois keeps ​Inter at bay

Real coach Jose Mourinho faced his former club at the stadium where he guided Inter to Champions League glory against Bayern Munich in 2010, but ​the visitors threatened to spoil his evening.

Courtois repeatedly came to Real's rescue against an Inter side who arguably had the better of the ⁠contest, controlling more than 64 percent of possession but paying for two costly defensive errors. The Belgian made a string of saves throughout the match to help preserve the hosts' narrow ​victory.

Real went ahead when Mbappe pressured Yann Bisseck into losing possession and Brahim Diaz collected the loose ball before feeding the French striker who sent it beneath the goalkeeper.

Courtois then saved ​Hakan Calhanoglu's powerful free kick before Inter goalkeeper Martinez gifted Real their second, attempting to dribble past Valverde inside his goal area and allowing the midfielder to poke the ball home.

Jude Bellingham missed a close-range chance before halftime and Inter maintained their pressure after the break. Carlos Augusto converted Lautaro Martinez's low cross in the 76th minute but Real held on.

"I think we played a great first half but I ​don't deserve the MVP award today – Courtois deserved it because he saved us with an extraordinary performance," Valverde told Spanish broadcaster Movistar Plus.

Haaland breaks through

City controlled possession against Porto and ​finished with 20 shots, including 10 on target, while the hosts failed to register a single attempt. Maresca's side had more than 70 percent possession and forced Porto's goalkeeper into six saves before halftime but ‌had to ⁠wait until after the break for the breakthrough.

Haaland broke the deadlock two minutes after the restart, heading Enzo Fernandez's lofted cross into the top corner. He added his second goal a minute into stoppage time, finding the bottom corner from Rayan Ait-Nouri's pass.

“I think we could've scored more goals, especially in the first half but overall I think we deserved to win the game," Maresca told Amazon Prime.

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"We didn't concede a lot. It's normal to come here and concede some chances because it's normal, so overall happy with the performance."

Betis trailed to Lille's ​12th-minute opener before Bartra equalized from Fornals's cross. ​Alexsandro restored the hosts' advantage three ⁠minutes later following a corner.

Bartra headed in Isco's free kick in the 49th minute and Parrott completed the turnaround five minutes later with a low strike after an individual run. Mbappe was subsequently dismissed following a VAR review for elbowing Natan.

Dortmund went ahead through Veiga's attempted ​clearance in the 53rd minute before Villarreal levelled with a close-range header in the 66th. Guirassy restored the lead from Fabio Silva's ​pass in the 80th ⁠and converted a penalty four minutes later after being fouled, before scoring an own goal in added time while trying to help in defense.

Torres helps Villa hold off Brugge

In Belgium, Torres set up John McGinn to put Aston Villa ahead against Brugge in the 11th minute but Hugo Vetlesen equalized for the hosts eight minutes later.

Villa responded swiftly, with Emiliano Buendia restoring their lead from ⁠a Joao Gomes ​assist before Nicolas Jackson made it 3-1 just before halftime, Torres again supplying the final pass.

Brugge dominated after ​the break and Nicolo Tresoldi pulled a goal back with a penalty in the 61st minute but Villa protected their advantage to secure all three points.

Marin provided the decisive moment for AEK in the 21st minute against Austria's ​LASK, curling a free kick from outside the penalty area on the left-hand side into the top corner beyond the goalkeeper's reach.