PARIS: The 2025 Diamond League series will begin in Xiamen on April 26, organisers said on Wednesday, in a season in which it faces a challenge from a lucrative new US format. Diamond League organisers have already raised the prize money on offer for next season, partly in response to the purses announced by the four-meeting Grand Slam Track series backed by Olympic legend Michael Johnson. Johnson has promised to bring together “the best of the best” in head-to-head clashes and Grand Slam Track has already signed up a number of champions from the Paris Olympics including women’s 400m hurdles winner Sydney McLaughlin-Levrone. The 15-meeting Diam­ond League has increased its prize money to $9.24 million in 2025, while Grand Slam Track says it will have a prize fund of $12.6 million. The Diamond League season culminates in a two-day final in Zurich on Aug 27-28.