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The Manchester United loanee started alongside Robert Lewandowski and Raphinha in the Blaugrana's attack, with Lamine Yamal absent due to a groin injury.

He repaid Flick's faith by scoring his first two competitive goals for the club in a 2-1 win, planting a 58th-minute header into the bottom-left corner, then firing a wonderful effort off the underside of the crossbar and in.

Anthony Gordon pulled one back late on, but Barca navigated eight minutes of stoppage time to ensure a winning start, ahead of a match-up with Paris Saint-Germain on matchday two.

Rashford became just the second Englishman to represent Barca in Europe, after Gary Lineker scored six goals in 24 appearances for the Blaugrana from 1986 to 1989.

He is just the second Englishman to score on his Champions League debut for a non-English club against a Premier League team, after Harry Kane did so for Bayern Munich against Manchester United in 2023.

Flick was delighted to see Rashford get up and running for his loan club after a difficult few years at Old Trafford.

"I expected it, but I'm really happy for him," Flick said. "He did not have an easy few years. I've followed him, and I was always like, 'what kind of player is he?'

"He showed it in training. For me, it's the next step. The confidence he's got from these two goals, maybe he can make the next step.

"For a striker, it's important to score goals. He created a lot of chances in the first half, but to finish is an important thing. He did that today and we love that he did it in this way."

Rashford had six shots, 10 touches in the opposition box, made five dribbles and created two chances at St James' Park, the first time he has reached all those totals in a single Champions League match. 

"I'm learning a lot, it's a new style of football," Rashford said. "But it's making me a better player. Honestly, it's an amazing experience.

"I've always been a huge admirer of Barcelona, every player my age has watched them play amazing football.

"There was a split second where I could spot a gap [for the second goal]. I could see the far post and gave it a bit of lift, I aimed high and I knew when I caught it, it would take something special for the goalkeeper to stop it.

"I'm motivated, determined, the quality here is exciting. The team is so young, it's refreshing. We know how tough the competition is, so this year, it's about improving and trying to go one step more."