'Barcelona made a mistake!' - Marc Guiu's first Chelsea hat-trick sees La Liga giants come under fire for £5m sale of wonderkid striker

Guiu's sensational performance inspired Chelsea to a 5-1 win over Shamrock Rovers in the Conference League. Chelsea head coach Enzo Maresca opted for a rotated lineup following a vital Premier League win over Brentford that brought the Blues within two points of leaders Liverpool. Given the chance to lead the line, Guiu capitalised on a defensive error in the 22nd minute to score his first of the night. Despite the visitors equalising through Markus Poom, Guiu struck twice more before half-time, cementing Chelsea’s commanding lead.

Guiu first made headlines at boyhood club Barcelona last season, scoring on his La Liga debut against Athletic Club after emerging from the prestigious La Masiaacademy. In July, Chelsea triggered his £5 million (€6m) release clause, signing him to a five-year deal with an optional extra year. The move raised eyebrows on Barca's part given his talent and potential, and Guiu’s performances since have only amplified those questions.

Speaking on TNT Sports after the match, former Chelsea star Cole expressed amazement at the teenager’s potential and Barcelona’s apparent oversight to let him walk away without much of a fight.

"My thought with Mark Guiu is, how did Barcelona let him go?" Cole questioned. "When I watch him play, and he's 18 years of age, this kid, in two years time could be an established, unbelievable No 9. I think he could go all the way because I watch him and and all the things that you can't teach he's already got. He knows when to go in the box, his instincts, his aggression, he's brave. He can brush up on all the other things in his game. And at 18, he's playing with a smile on his face, you know, I think Barcelona made a real, real mistake there."

Despite limited opportunities in domestic competitions, with just one substitute appearance in the Premier League against Manchester City, Guiu has flourished in Europe. His six goals in the Conference League demonstrate his potential to become a pivotal player for Chelsea.

The Blues have undergone a remarkable turnaround under Maresca. Mocked earlier this year for their oversized squad, Chelsea are now serious contenders for both domestic and European honours. They return to action against Everton on Sunday at Goodison Park.