Marc Guiu, 17, scores winner on his Barcelona debut, just seconds after coming on as a substitute

La Masia graduate Marc Guiu scored just 33 seconds into his senior debut to give Barcelona a crucial win in their La Liga clash against Athletic Bilbao – and it really is the script of dreams.

The 17-year-old forward, born in 2006, replaced highly-rated midfielder Fermin Lopez in the 79th minute of Sunday's game at the Camp Nou.

And moments later – with his third touch of the game – Guiu became the youngest player to score on his debut for Barcelona in the 21st century, when he showed great composure to beat Bilbao goalkeeper Unai Simon.

It was Guiu's first shot in his first ever game of senior football. Just let that sink in.

As you can imagine, the scenes after he scored were quite something. The camera soon panned to Frenkie de Jong and Robert Lewandowski, who were on their feet to applaud Barca's new star.

And soon, footage emerged of Guiu's family, overwhelmed by what they'd just witnessed in front of over 90,000 fans.

"I can't believe it. I'm out of breath, enjoying the moment," the 17-year-old told Esports 3 in his post-match interview. "This is unimaginable. I've been working all my life to take advantage of opportunities and it's come to me.

"Joao Felix controlled the ball, I saw that there was space behind the defence, he gave it to me and I beat Unai Simon. It's an honour to have scored a goal against a goalkeeper of his calibre."

He added: “Xavi had told me to be ready, that I would get my chance. I’ve dreamed of this moment for almost every night of my life. My teammates told me to enjoy this moment. I won’t be able to sleep tonight.”

Barca manager Xavi was full of praise for the teenager, and backed his decision to promote from the famous La Masia.

"I personally like Marc Guiu. I've always said that I have no problem looking at La Masia players," he said. "You have to give them trust. When you see that the kid is ready, you take him to the playground."

He continued: "Guiu's face on the bench didn't look scared. He was looking at me with the 'coach, put me on!' face. I saw that he was ready and I subbed him in. You can tell that he can score goals, and everything went well. I'm so happy."

The Catalan giants are now within a point of leaders Real Madrid ahead of the much-anticipated El Clasico on Saturday. Will Guiu get some minutes after his display against Bilbao? Only time will tell.

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