Xabi Alonso plans to discuss Dani Carvajal's conduct after his inexplicable red card almost cost Real Madrid in their Champions League opener against Marseille.

Carvajal had a chance to impress after Trent Alexander-Arnold was forced off injured just five minutes into Tuesday's clash, but instead left Madrid to snatch an opening victory with 10 men.

The full-back lunged his head towards Marseille goalkeeper Geronimo Rulli, leaving Irfan Peljto with little choice to show a 72nd-minute red card after consulting the touchline monitor.

Kylian Mbappe spared his team-mate's blushes, as he converted his second penalty of the game to claim a 2-1 win at the Santiago Bernabeu, though Alonso was left unimpressed with Carvajal's conduct.

"The dismissal was avoidable, it's a shame," Alonso said on Spanish channel Movistar+. "We'll have to talk about it."

Mbappe, at least, ensured Carvajal's dismissal would only be a talking point, rather than the entire focus of Alonso's first Champions League game in charge at Madrid.

The France star, who cancelled out Timothy Weah's opener in the first half, has now scored 50 goals in 64 appearances for Madrid across all competitions, becoming the fastest player to reach a half-century of goals for the club since Cristiano Ronaldo in November 2010 (51 goals in 54 matches).

"He's in his best shape, with two goals," Alonso said of Mbappe, who has also scored four times in as many LaLiga games to start the 2025-26 campaign.

"I'm happy to be with him, day in and day out, because we have a lot left to do."

Madrid accumulated a massive 3.65 expected goals in a dominant showing, with 11 first-half shots on target their most in an opening 45 minutes of a Champions League clash since data collection began in 2003-04.

They also finished with 15 attempts on target, which is their highest tally in a coach's Champions League debut since the 2003–04 season.

Alonso felt his side were good value for their victory, despite the "crazy" ending after Carvajal's mindless clash with Rulli.

"The first half-hour was very good, with many chances," the former Bayer Leverkusen boss added. "We could have taken the lead, but we conceded and then everything became level.

"We were pushing until things got complicated with Carva's sending-off, but the team showed their desire, their Champions League spirit.

"We didn't back down; we wanted to win. And that spirit allowed us to defend with 10 men and hardly have any trouble."

Marseille have now lost five games against Real Madrid in the Champions League/European Cup, their joint-most defeats against any side in the competition (also five against Porto).

Weah offered hope of overturning that poor record, with his 22nd-minute effort making him the first player since Gabriel Heinze against AC Milan in 2009 to score on his Champions League debut for Marseille.

But the French giants were unable to find a decisive second goal, even after Madrid were reduced to 10 men, much to Roberto De Zerbi's frustration.

"We played a good game. Even if we were a little too timid, especially at the start of the match," the Marseille head coach told Canal+.

"We were better in the second half of the first half. I'm especially disappointed because after the red card, I would have liked to see my team advance more, create more chances and do more to try to win."