Horsfield was the medalist at the 2017
European Tour Qualifying School to earn a place on the European Tour for 2018. He had a useful start to 2018, with a 4th place in the
ISPS Handa World Super 6 Perth and finishing second at the
Tshwane Open, two strokes behind
George Coetzee. Later in the season he was tied for 5th place in the
Sky Sports British Masters and finished 52nd in the Order of Merit. In early August
2020, Horsfield had his breakthrough win on the European Tour when he won the
Hero Open by one shot over
Thomas Detry. Two weeks later, Horsfield won his second European Tour event at the
Celtic Classic in Wales, two strokes ahead of Detry, who finished as runner-up again. In May 2022, Horsfield picked up his third European Tour victory at the
Soudal Open in Belgium. Horsfield was part of the inaugural
LIV Golf event at
Centurion Club at London, where he placed 5th, winning $975,000. He collected a total of $3.5 million in individual prize money across the
2022 and
2023 LIV seasons, despite missing most of the 2023 season due to hip surgery. ==Amateur wins==