|Venue: Zurich Dates: 8-9 September BBC coverage (UK only): Watch on BBC Two, BBC iPlayer and the BBC Sport website and app from 16:30-18:30 BST on Wednesday and 18:00-21:00 BST on Thursday|
Burundi's Francine Niyonsaba said she "did what I had to do" after beating Kenyan rival Hellen Obiri to win the 5,000m Diamond League final in Zurich.
The 28-year-old, who was disqualified from the 5,000m heats at Tokyo 2020, proved too strong in the home straight, winning in 14:28.98.
Niyonsaba used to specialise in 800m, but switched events after testosterone limits were introduced in 2018.
"I am still learning after switching," she said. "I did what I had to do."
Niyonsaba won world and Olympic silver medals at 800m before World Athletics brought in new regulations in 2018 that required women with differences in sexual development and higher-than-usual testosterone levels to take hormone-altering medication or be barred from distance events between 400m and a mile.
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Niyonsaba opted to take on longer distances and, after the disappointment of a lane infringement ending her 5,000m Olympic campaign, she has become a genuine threat in her new discipline with an impressive set of late-season results.
"I am no longer an 800m [runner], I am a long-distance runner," she said after her win over world champion and Olympic silver medallist Obiri on a specially-constructed street track around Zurich's biggest city square.
"I stayed behind most of the race, these were my tactics. I have a lot of resilience and determination."
When it was suggested World Athletics could broaden the range of events covered by it's controversial testosterone limits, Niyonsaba joked she was ready to switch again.
"I can go to pole vault! Or high jump!" she added.
Elsewhere on the banks of Lake Zurich, the city-centre crowd saw American world record holder Ryan Crouser win his first Diamond League title as 22.67m proved enough to see off compatriot Joe Kovacs in the shot put.
Britain's Jazmin Sawyers came close to her 6.90m personal best, with a 6.74m leap good enough for fourth behind Serbia's Ivana Spanovic in the long jump.
Scot Andrew Butchart finished down in eighth in a men's 5,000m race won by Ethiopia's promising Berihu Aregawi.
Aregawi, 20, clocked 12:58.65, backing up an impressive showing in Lausanne last month where he pushed Olympic 1500m champion Jakob Ingebrigtsen close over 3,000m.
Russian Olympic champion Mariya Lasitskene won the high jump title with a clearance of 2.05m, a centimetre more than she required for victory in Tokyo.
The second and final night of the Diamond League final takes place in Zurich's Letzigrund Stadium on Thursday, with Britain's Dina Asher-Smith going up against Olympic champion Elaine Thompson-Herah over 100m.
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