World champion sprinter Justin Gatlin ended a 100m race limping and holding his left thigh just three weeks ahead of the defence of his title at the Doha world championships.
In the race at Croatian capital Zagreb the 37-year-old Gatlin suddenly winced in pain around the 80m mark, finished fourth with a time of 10.29sec and left the track supported by a fellow athlete.
Another American Michael Rodgers won the race with a wind assisted 10.04sec time.
The veteran sprinter, the 2004 Olympic 100m gold medallist who served a doping ban between 2006-10, is a long-standing fixture on the track who continues to show his enduring prowess.
Gatlin won world gold in London in 2017 ahead of fellow American Christian Coleman -- in the spotlight after charges were dropped against him for missing three drugs tests -- and now-retired Jamaican sprint legend Usain Bolt.
Not only is Gatlin plotting to defend his title in Doha, but he is using that as a handy warm-up for a fourth Olympic Games campaign at Tokyo 2020.