Wednesday's qualifying rounds took an unexpected turn with a mix of chaos on the track and field.

A four-man pileup marred the first men’s 5,000-meter heat, a cameraman wandered into the fray in another race and leg cramps and missed attempts added to the drama in the high jump.

The most dramatic moment unfolded in the first of two men’s 5,000 heats when Britain’s George Mills and France’s Hugo Hay exchanged elbows, triggering a domino-like pileup involving Mills and three other runners.

Post-race, tensions flared as Mills jabbed his finger at Hay, who, despite the earlier contact, stood his ground and pushed back.

"He took me out," said Mills, the British silver medalist at the European Championship in June. "He could have stepped out."

Mills, who finished 18th in the race due to the crash, said he figured that because "Hay is French and we’re in France" he had little chance of advancing to the final. However, the referee determined Mills and the three others were disadvantaged by the contact and moved all into the final.

There was more drama in the second heat when a cameraman wandering across the racing surface stepped into the path of the runners midway through the race. Everyone changed course without incident, but heading into the final stretch, American runner Abdihamid Nur, a medal contender, fell and finished last.

About the only thing that went as expected was two-time world champion Jakob Ingebrigtsen of Norway qualifying first in 13:51.59. Ingebrigtsen was competing less than 15 hours after a stunning performance.

In the high jump, Gianmarco Tamberi and Mutaz Barshim, who famously shared gold in Tokyo, took their friendship to a new level during a difficult qualifying round.

Both advanced despite physical issues. At one point, with Barshim writhing in pain from what appeared to be a calf cramp, Tamberi came over and massaged his buddy’s leg. Later, medical staff took over.

Barshim finished in good shape, clearing 2.27 meters to advance to Saturday’s final.

Both men could use some rest.

"Nothing is good right now," Tamberi said.

Tamberi has already had an eventful Olympics, including carrying the flag for Italy during the opening ceremony. He then returned home and was hospitalized for what he described on Instagram as a "probable" kidney stone issue and a fever of 38.8 Celsius (101.8 Fahrenheit).

Back in Paris, Tamberi cleared 2.24 meters despite touching the bar slightly on his second jump. He missed all three attempts at 2.27 but qualified because only one man in his qualifying group, Hamish Kerr, cleared that height.

In the women’s 100 hurdles, Michelle Jenneke of Australia got tripped up going over the third barrier. She got up and continued competing in the wrong lane, clipped the fourth hurdle, but managed to finish, advancing to the repechage round.

Defending champion Jasmine Camacho-Quinn of Puerto Rico qualified with the morning’s best time, 12.42 seconds.

There was less drama in the men’s 800 heats, where world silver medalist Emmanuel Wanyonyi of Kenya led with 1:44.64. Tokyo silver medalist Maria Andrejczyk of Poland led the women’s javelin qualifying.

The Spanish pair of Alvaro Martin and Maria Perez won the race walk mixed relay ahead of teams from Ecuador and Australia.

Later, medals were to be handed out in the women’s pole vault, men’s discus, men’s 400 and men’s 3,000 steeplechase.

Also, Noah Lyles was set to race in the 200 semifinals as he attempted to complete a sprint double after his earlier performance.