Barcelona boss Ronald Koeman was impressed by Ansu Fati's impact in Sunday's season-opening 4-0 win over Villarreal but he tempered excitement around the teenager as he revealed pre-season concerns.
Fati, 17, was in devastating form for Barca at Camp Nou as Villarreal were swept aside, scoring two fine first-half goals in a five-minute period, before then winning a penalty that was converted by Lionel Messi.
With Messi's future seemingly unclear, Fati had been billed as the poster boy of a new era at Barca – fittingly it was the Spain international who got the ball rolling in style.
And while Koeman was impressed – the Dutchman had been shown beaming as he embraced Fati after his 70th-minute withdrawal – he was keen to remind both the player and fans that the youngster still has much to learn.
"We must highlight the game and performance of Ansu Fati," Koeman told reporters. "I was complaining a little last week about him not having the maximum level of performance in the pre-season.
"He is only 17 years old, he will have a great future, but he must improve things. Sometimes he lacks a bit of concentration.
"One of my criticisms was in the friendly against Elche – he was not good. Today he was. His intensity out wide was immense, he played a great game and we took advantage of his qualities."
After Luis Suarez departed Barca to join Atletico Madrid – where he had a dream debut on Sunday – Koeman said that he didn't feel Barca necessarily needed to bring in another striker, but would also welcome a new No.9.
"It is always good to have another striker for having another plan," Koeman said. "it is true we can play without a striker, we have worked on how to exchange positions and to be deep when attacking, but it is important to have other possibilities. We are working and I hope we can occupy the position of the nine."
Sergio Busquets hit a similar note as his manager, stressing the need for patience with Fati.
"We have to be calm with him, we know the potential he has," he told Movistar. "He is tremendous for his age, but we don't want to get too far ahead of ourselves.
"He has many team-mates from whom he can continue to learn so that his ceiling is as high as possible.
"You have to let him play his football and take advantage of the fact that he is at a good point."