Atletico Madrid kicked off their La Liga campaign with a 1-0 win over Getafe in a match that saw both teams reduced to 10 men in the first half at the Wanda Metropolitano Stadium.
Sevilla also got off to a winning start under new manager Julen Lopetegui on Sunday. Goals from Sergio Reguilon and Nolito were enough to see off Espanyol at the RCDE Stadium.
Sunday's other La Liga fixtures saw Alaves beat Levante 1-0, while Real Valladolid won at Real Betis.
Here is a look at the La Liga standings after the first round of fixtures:
Alaves 1-0 Levante
Espanyol 0-2 Sevilla
Real Betis 1-2 Real Valladolid
Atletico Madrid 1-0 Getafe
Atletico Madrid handed record signing Joao Felix his La Liga debut against Getafe, but it was Alvaro Morata who opened the scoring midway through the first half.
The striker headed a Kieran Trippier cross past goalkeeper David Soria to give Diego Simeone's men the lead on 23 minutes.
An entertaining first half saw both teams reduced to 10 men before the break. Jorge Molina was handed a straight red card after a video assistant referee review for a foul on Thomas Partey.
Sports journalist Jonas Giaever offered his view:
Jonas Giæver @CheGiaevara
That's nasty from Jorge Molina on Thomas Partey. Difference between that one, and the one Luka Modric gets sent off for yesterday is that Molina trails Thomas. Modric misses the tackle and it becomes worse, Molina has no other intention than stopping Thomas illegally. Gruesome.
Atletico full-back Renan Lodi followed just three minutes before half-time. He picked up his second yellow of the match after an aerial clash with Damian Suarez.
Felix lit up the Wanda Metropolitano Stadium in the early stages of the second half. The 19-year-old produced a jinking run from inside his own half that ended with him winning a penalty:
Morata stepped up to take the kick but put his shot too close to a diving Soria, who managed to tip the ball around the post.
Meanwhile, Felix's debut came to a premature end after an injury forced him off and Marcos Llorente replaced him:
Getafe came close to an equaliser when Angel Rodriguez fired an effort against the woodwork, but they could not find a way past goalkeeper Jan Oblak and slipped to a first defeat.
Sevilla have enjoyed a busy summer in the transfer market, and one of their new arrivals put them ahead against Espanyol in their opener.
Full-back Reguilon, on loan from Real Madrid, lashed home from inside the box on 44 minutes after goalkeeper Diego Lopez saved Luuk de Jong's header.
The 22-year-old was a threat throughout the match down the left flank in an impressive showing:
Espanyol improved after half-time and were awarded a penalty after Diego Carlos was adjudged to have handled the ball. However, VAR overturned the decision.
Sevilla sealed the victory with just four minutes of normal time remaining. Nolito dribbled past his defender and fired a low finish past Lopez.
Alaves saw off Levante thanks to a debut goal by striker Joselu. The striker, who arrived from Newcastle United in the summer transfer window, headed home the only goal of the game on 54 minutes:
The result means it is also a winning start for Alaves manager Asier Garitano. The 49-year-old took over the club in May following the departure of Abelardo Fernandez.
However, Real Betis boss Rubi tasted defeat in his first game in charge of the Andalusian side at the Benito Villamarin Stadium against Real Valladolid.
The hosts suffered an early blow when goalkeeper Joel Robles was sent off for bringing down Sandro Ramirez after only eight minutes.
Yet Valladolid had to wait until the second half to take advantage and break the deadlock. Sergi Guardiola opened the scoring on 63 minutes, but Betis hit back five minutes later through Loren Moron.
The game looked to be heading for a draw until Oscar Plano found an 89th-minute winner for Valladolid to secure all three points for the visitors.