The Chelsea head coach spoke ahead of a decisive week for the club, following an important league win at the weekend and the start of a crucial European double-header.

Guiu, who created Enzo Fernandez's late goal against Burnley after coming off the bench in the 2-0 win, has caught Maresca's attention once again. With Chelsea meeting his former club tonight, the spotlight naturally fell on the 19-year-old.

"Marc is doing really well," Maresca said. "He was here last season and had the chance to play a lot, and then he got injured. He is growing, he is improving. At the start it was a bit difficult because of injuries, but he is working very hard and we are very pleased with him. He is young; he needs to keep learning so he is ready when the opportunities arrive."

Guiu's impact has already increased competition up front. Liam Delap, who has started regularly, will feel the pressure if he does not rediscover his scoring touch. Maresca has also preferred using Joao Pedro in more fluid central roles, and Guiu's energy off the bench is giving Chelsea's attack a sharper edge.

Maresca Shuts Down Estevao-Yamal Debate

The Chelsea head coach was also asked about comparisons between teenage wingers Estevao Willian and Barcelona starlet Lamine Yamal. Maresca avoided the narrative entirely.

"Estevao is going to be an important player in the future, no doubt," he said. "But he has to enjoy football, be happy, and not think about being better than one player. For sure, he is going to be a top player for this club."

Maresca refused to get drawn into tactical hints, praising Barcelona while keeping Chelsea's plans quiet.

"Barcelona are playing in an amazing way; you always learn from Barca," he said. "The way they attack, the way they defend… they won the league last season. They are a good team and they always have the initiative, and we will try to do the same on our side."

Cucurella Ready for Yamal Test

Maresca was also asked how Chelsea intended to contain Yamal's movement between the lines. Rather than focus on the teenager's threat, he highlighted Marc Cucurella's consistency.

"Cucu is a big advantage for us always, not just tomorrow," Maresca said. "His level has been amazing since I've been at the club. Not just defending, but as part of our game, he is a big value and we are very pleased with him. They have quite a few players we need to face as a team."

Cucurella, who came through Barcelona's academy and is now a regular for Spain, will be desperate to impress against his old club. His duel with Yamal promises to be one of the defining battles at Stamford Bridge tonight.

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