Betis - arriving in the Spanish capital after confirming their place in the league phase of the UEFA Conference League on Thursday - had the first real chance of the game when summer signing Romain Perraud fizzed in a cross that was nodded over at close range by former Barcelona youngster Abde Ezzalzouli.
The hosts responded through Eder Militao as the centre-back leapt to meet a corner from Rodrygo, but the effort was parried by Rui Silva before Perraud did enough to prevent Militao from diverting the rebound on target.
Despite having the majority of possession, Los Blancos weren’t in full control of the contest. Nonetheless, the partnership between Vinicius Junior and Mbappe almost bore fruit, with the jet-heeled Frenchman nearly getting on the end of a delightful through ball from the Brazilian, which if it had been converted, would have been a goal-of-the-season contender.
Then, in first-half stoppage time, Mbappe’s eyes lit up as Dani Carvajal’s cross travelled in his direction, but Youssouf Sabaly slid in to intercept superbly.
Both teams emerged unchanged after the break, but shortly before the hour mark, Manuel Pellegrini brought on Johnny Cardoso and Barca loanee Vitor Roque - the latter for his club debut.
Vitor Roque had an immediate impact, forcing Thibaut Courtois into a save from Sabaly’s cross. At the other end, Diego Llorente was having one of the matches of his life as he made another important intervention in what had become a breathless end-to-end encounter.
However, he was a bystander on 67 minutes as Federico Valverde’s exquisite flick released Mbappe, who buried the invitation to send the Bernabeu berserk.
Vinicius had started to cut a frustrated figure in the second period after hitting the woodwork and feeling that a few decisions had unfairly gone against him, but he was vindicated by a VAR check after being brought down by visiting goalkeeper Silva, with Mbappe dispatching the spot-kick.
Real Madrid may have begun the season below their usual standards performance-wise, yet they head into the international break in second place, albeit four points behind league leaders Barcelona.
Betis, meanwhile, find themselves just above the relegation zone, but can console themselves in the knowledge that they have a game in hand on most teams in the division at this early stage of the campaign.
Flashscore Man of the Match: Federico Valverde (Real Madrid)
