A Roma-born youngster, Leoni’s formative years were spent away from the capital after his family relocated to Padua when he was five. He progressed through the youth systems of Vigontina, Cittadella, and eventually joined Padova’s academy. In March 2023, just three months after his 16th birthday, he made his senior debut for Padova in Serie C — the youngest professional debutant in Italy that season. In February 2024, he joined Serie B side Sampdoria on loan, and under the guidance of the legendary Andrea Pirlo, made 12 league appearances and scored his first professional goal, against at Palermo on 6 April in a 2-2 draw in Serie B. Sampdoria bought Leoni on 1 July 2024 for £1.3 million, activating a buyout option that was part of his loan agreement, but only six weeks later sold him to Parma for £4.1 million plus £3.1 million in add-ons! A shrewd piece of business by Sampdoria at the time — and, as it turned out, an equally astute investment for Parma!

In the 2024/25 season, Leoni featured in 17 league games, scoring once as he began to establish himself among Italy’s most exciting young players. Standing 6′5″ (196 cm), Leoni combines athleticism, tactical awareness, and composure on the ball. He is strong in duels and dominant in the air, and already cuts an imposing figure for his age. Comfortable playing progressive passes, Leoni recorded close to 88% pass accuracy while showing mobility in building attacks from the back. Such qualities, rare in an 18-year-old centre-back, drew Liverpool’s attention despite his limited top-flight experience. The Reds paid £26 million plus £3.4 million in add-ons for Leoni in August 2025 — a remarkable fee for a player with so little senior football on his CV, underlining just how highly he is valued at Anfield.

Leoni is a rare blend of youth, physicality, and footballing intelligence, possessing both the raw tools and the mentality to evolve into a world-class centre-back. He arrives on Merseyside not as a finished product but as a high-ceiling talent, primed to benefit from the mentorship of Virgil van Dijk and the demanding environment of Liverpool’s backline.