Marcus Rashford scored twice as Barcelona kicked off their Champions League bid with a 2-1 victory away to Newcastle United on Thursday, while Erling Haaland notched his 50th goal in the competition in Manchester City's win over Napoli.

The third consecutive evening of action in the first round of games in this season's league phase also saw Eintracht Frankfurt, Sporting Lisbon and Club Brugge record big wins while FC Copenhagen held Bayer Leverkusen.

Rashford was still looking for his first Barcelona goals following his July loan move from Manchester United, and he got off the mark by heading in Jules Kounde's cross just before the hour at St James' Park.

The England international then doubled the Spanish champions' lead with a ferocious right-foot shot from outside the area high into the top corner midway through the second half.

Anthony Gordon pulled one back for Newcastle, but Barcelona – beaten in the semi-finals last season – held on to claim their first three points of the campaign.

"It's an amazing experience playing for Barcelona. I've always been a huge admirer of the club. We just want to win as much as possible," Rashford said.

Pep Guardiola's City, the 2023 Champions League winners, got off to an ideal start too as they saw off Serie A champions Napoli, claiming a 2-0 victory at the Etihad Stadium.

The game was conditioned by the sending-off midway through the first half of Napoli captain Giovanni Di Lorenzo, dismissed for wiping out Haaland as the Norwegian headed towards goal.

That led to Napoli coach Antonio Conte taking off Kevin De Bruyne just 26 minutes into the Belgian playmaker's return to the stadium where he starred for a decade before departing at the end of last season.

Haaland then gave City the lead as he nodded in from a delightful Phil Foden assist early in the second half. That took him to 50 career Champions League goals from just 49 appearances.

Jeremy Doku then made it 2-0, leaving Napoli without a win in 13 visits to face English opposition in European competition.

"The numbers speak for themselves and how fortunate we are to have him," Guardiola said of Haaland, who is 12th in the all-time Champions League scoring charts – barely over a third of the way to Cristiano Ronaldo's record 141 goals.

"Along with the two monsters of the past 15 to 20 years Ronaldo and (Lionel) Messi, Erling is there. In terms of goals he is unbelievable," insisted Guardiola. (AFP)