The men's 200m final exploded in bizarre controversy after England's Zharnel Hughes flirted across his rival's lane and then slowed down in the final 30m – only taking the victory by a debatable photo finish.
In a storm of controversy, Hughes was more than halfway around the stadium completing his victory lap when he was dramatically informed he'd been disqualified.
Hughes and Trinidad and Tobago's Jereem Richards finished with the same time 20.12, but the photo finished showed Hughes hit the line first by the smallest of margins.
The crazy finish only happened after Hughes slowed considerably in the final metres with some commentators declaring he appeared to think he was safely home.
With commentators stunned by Hughes' bizarre finish, replays showed he clearly crossed into Richard's lane, forcing his rival to change his line.
There was also arm contact between the two as Richards made a desperate late lunge 10m before the line.
"It's unbelievably close, it is just crazy what happened in the last 10 meters," McAvaney told Seven.
"Not sure exactly how it played out, how does it finish? Wow, what a race.
"It was almost like they were going to fall over.
"I would be fascinated to see the front angle and I can only conclude they just collided. Actually when he crossed the line, Hughes grabbed his hand."
English athletics champion Lord Sebastian Coe said it was obvious there would be a protest to Hughes' run after watching the front-on angle.
There was no need for a protest with officials taking the decision to disqualify Hughes - several minutes after the event finished.
He had no idea.
"Hughes didn't know and that is remarkable," McAvaney said.
"On the board, he has done a lap of honour and now there is disbelief for the young man. I am sure England will do everything they can do to get him reinstated."
Coe said there could be a technicality in the rule book which would allow England to protest the disqualification.
"I would be surprised if they did not appeal this," he said.
"I am not on the jury. I have sat on juries of appeal for many years, but you are right, you can run on the line and you could be 3m ahead and run on the line and there is no material advantage, but if you do happen to impede or clash that will be the argument.
"The jury of appeal however has a problem because two or three of those members are actually conflicted because the places and the
decisions are concerning their own athletes. It may well be that they will have to chase them around at the moment."
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