MOSCOW — Ashton Eaton of the United States ran a blistering 400 meters to regain the lead after the first five events of the decathlon Saturday, while defending champion Trey Hardee dropped out with a hamstring injury at the world championships.
The world-record holder clocked 46.02 seconds to run the fastest decathlon 400 at a world championships, according to the IAAF.
Eaton holds with a slim lead of 4,502 points to American Gunnar Nixon's 4,493. Michael Schrader of Germany fell to third with 4,427.
The start of the grueling two-day event shaped up as a thrilling showdown between two Americans, Eaton and the 20-year-old Nixon. Hardee, the two-time defending champion and Olympic silver medalist, failed to earn points in the high jump and withdrew.
Hardee developed cramps in his hamstring and missed all three high jump attempts. He was fifth after three events and needed a good performance in the high jump to stay in medal contention.
"It was just one of those things, landed on the pit after my second attempt, my hamstring was grabbing," Hardee said. "I laid there and tried to keep it from cramping up. The third (attempt) came around way too quick."
Nixon, the junior world champion, cleared 7 feet, 1-4 in the high jump to seize a big lead after four events. But Eaton surged back with his fast 400, only 0.39 seconds off his personal best.
Nixon had led Schrader by 110 points and Eaton by 116 after the high jump.