Chelsea have completed the signing of midfielder Mario Pasalic from Croatian club Hajduk Split.
Under-21 international Pasalic, 19, was named in his country's provisional 30-man squad for the World Cup, but did not make the final 23.
That followed a season in which he scored 11 goals in 36 senior appearances, attracting the attention of several clubs.
But he said he opted to move to Stamford Bridge because Blues midfielder Frank Lampard is his hero.
"I am very happy because I am now a Chelsea player," he told Chelsea's official website. "I am very impressed by the training ground, and I must thank everybody at Hajduk. This is now a new start in my career.
"I am a central midfielder, my favourite player is Frank Lampard, and so I am very happy to be a Chelsea player."