Si reached the first ranking final of his career at the following season’s 2024 German Masters, but lost 5–10 to Judd Trump. At the 2024 World Championship, he defeated Mark Williams 10–9 in the first round and then lost 9–13 to Jak Jones in the last 16.The 2025 Masters marked his first appearance at the tournament, but Si lost in the first round to Mark Allen 2–6. At the 2025 World Championship, Si advanced to the quarter-finals where he was defeated by O’Sullivan 9–13