Paco Alcacer believes that his Borussia Dortmund team-mate Jadon Sancho has what it takes to become one of the world's best.
Sancho enjoyed a breakthrough campaign in 2018-19, scoring 12 Bundesliga goals and tallying 14 assists, the most of any player in the German top flight.
The England international has followed that up with a strong start to the current season, having already scored two and assisted three in just three league games thus far.
At 19, Sancho has become the youngest Bundesliga player to ever reach 15 career league goals.
Alcacer, who has had three of his four Bundesliga goals this season assisted by Sancho, has backed his team-mate to go on to achieve even bigger things.
"He's a kid, 19 years old, with great quality. If he keeps his head, he will be a top player," Alcacer told Sport.
"There's uncertainty at that age, but as a player and a person in the dressing room, he's top.
"If he improves and picks up other qualities, he will be one of the best in the world."
Alcacer has joined Dortmund permanantly after spending part of the 2018-19 season with the Bundesliga club on loan from Barcelona.
After struggling for form at Barca, the 26-year-old had a breakout season with Dortmund last term by scoring 18 goals in Bundesliga play.
Asked if this is the most confident he's felt in his career, Alcacer said: "It could be. The numbers suggest that. I feel confident and comfortable with my teammates -- which is a plus on the pitch.
"It's a question of confidence and feeling comfortable on the pitch. Minutes are important. The treatment from my teammates, having an understanding with them, that's also key."
Alcacer will get a chance to square off against his former club in this season's Champions League, as Dortmund have been drawn with Barcelona in Group F.
When asked if he would celebrate against his former club if he scores, Alcacer wouldn't rule the possibility out.
"I wouldn't know what to do, because at the end of the day you're really happy [to score]," Alcacer said.
"A lot of people behaved really well with me there, a lot of people also said things that you don't like, but the respect was always there."