On June 17, before he was about to face Harry Kane in Croatia’s opening World Cup fixture against England in Dallas, Luka Vuskovic was taking an important phone call.He was speaking to Serbia-based Nenad Sarcevic, his personal analyst, to prepare him for the challenge ahead. It is part of Vuskovic’s pre-game preparation that often takes place close to kick-off — on the team bus or in the dressing room, for example.Marco Boskers is Sarcevic’s boss at Smart 11, the Netherlands-based self-analysis app. He explains: “There are a few players that want to do analysis on matchdays. Luka will still do it when he’s on the massage table before the match. When the coach is already speaking to the players about what the plan is, he’s still doing sessions. That’s how crazy he is about getting sharp right before the match.”The England game did not go to plan for Vuskovic or Croatia. The 19-year-old centre-back was substituted midway through the second half of a 4-2 defeat (Kane had scored twice by that stage), but one of the hottest defensive prospects in world football was already well on the way by then to completing a £49million ($65.4m) move from Tottenham Hotspur to Brighton & Hove Albion.Brighton broke their transfer record — which stood at £40m for French forward Georginio Rutter from Leeds United in the summer of 2024 — to land Vuskovic. He did not kick a ball for Tottenham in a competitive fixture, but will be meticulously briefed for the tests awaiting him in the Premier League.It has been this way since October 2024 when Vuskovic linked up with Smart 11. At the time, Vuskovic was on loan to Belgian Pro League club Westerlo from Hadjuk Split — Tottenham had announced his signing in September 2023 when he was 16 years old, but he could not move to the UK until reaching 18 years of age in 2025.Vuskovic played just 66 minutes of Croatia’s World Cup campaign (Paul Ellis/Getty Images)Boskers went to Westerlo to watch client Edisson Jordanov, a German-born Bulgarian international, in a home game against Beerschot. He had previously known nothing about Vuskovic, who scored both goals for Westerlo in a 2-2 draw. “I thought: ‘This is crazy, a 17-year-old centre-back scoring two worldies’,” Boskers says. “Everybody in the stadium was speaking about him.