DOHA, Qatar (AP) — The Latest on the track and field world championships (all times local):
The 2012 Olympic champion Kirani James set the pace in the heats of the men's 400 meters, winning his race in 44.94 seconds.
Michael Norman of the U.S. and Emmanuel Kipkurui Korir of Kenya also set fast times to win their heats, but European champion Matthew Hudson-Smith of Britain's bid for a medal was ended by injury.
Hudson-Smith pulled up abruptly just after the start and collapsed with an apparent thigh injury. He was given medical attention and left the track in a wheelchair.
The reigning Olympic and world champion, South Africa's Wayde van Niekerk, is not competing because he hasn't fully recovered from a knee injury he suffered playing a charity tag rugby game in late 2017.
Once again, doping is overshadowing the action at the track and field world championships.
Less than 24 hours after renowned distance-running coach Alberto Salazar was banned four years for violations including possessing and trafficking testosterone, two athletes from his team will race in the men's 800-meter final.
Donavan Brazier and Clayton Murphy of the U.S., who have not themselves been accused of any wrongdoing, are among the medal contenders along with Ferguson Rotich of Kenya.
Salazar's credentials for the championships have been revoked and officials are formally notifying his athletes that they are forbidden from working with him.
Also Tuesday, Noah Lyles of the U.S. will battle Canada's Andre de Grasse in the 200 final, while medals are also up for grabs in the men's pole vault and women's javelin.
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