In the absence of his fiercest rival Lachie Kennedy, Australian sprinting sensation Gout Gout has claimed back to back national 200m titles — but not without an almighty challenge from Aidan Murphy.

The 18-year-old won his signature event in 19.86, well clear of Murphy (19.88) in second and Calab Law (20.21) in third at the Australian Athletics Championships in Sydney on Sunday.

WATCH THE VIDEO ABOVE: Gout Gout wins 200m national title with historic run

Murphy led Gout into the straight after an impressive bend from the underdog 22-year-old, but Gout kicked into gear in the final 100m and won by five metres.

“He has absolutely done what everybody thought he might, and he’s done it at 18 years of age,” Bruce McAvaney said on Channel 7.

“The world will be shaking. It is seismic. It is the exclamation mark of all time on a national championships that will be remembered forever.

“And he did it because he had a race; he wasn’t a certainty.

“And Murphy, can you believe it, has run 19.88. We’ve got two men inside 20 seconds. It’s hard to get your head around it.

“It’s historic, it really is. It’s a sporting moment; it transcends athletics and track and field.”

Olympic legend Usain Bolt’s fastest time under the age of 23 was 19.93. Only Erriyon Knight has ever run faster as an under-20.

“He’s gone past Usain Bolt by a big, big stretch,” McAvaney added.

Gout’s great rival Lachlan Kennedy wasn’t in the field, withdrawing from the event after clocking 9.96 for the second time in as many days to win his first national 100m title.

While Kennedy has punched his ticket to the Commonwealth Games, Gout won’t be in Glasgow after choosing to focus instead on the 200m at the world under-20 championships.

- With AAP

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