The Wallabies have received a big boost ahead of their Rugby Championship rematch against Argentina in Sydney, with fly half Tom Lynagh cleared of concussion.

There was confusion over the young playmaker following Australia’s last-gasp victory over the Pumas in Townsville, where Lynagh was replaced by James O’Connor.

The veteran piloted the home side to a 28-24 comeback win, with the match-winning try coming six minutes after the full-time siren.

Wallabies snatch thrilling victory with try six minutes after full-time

The Wallabies turned down three chances to take a draw after full-time, before scoring a match-winning try to down Argentina in Townsville. 

Lynagh left the field in the second half with hamstring tightness and also underwent a head injury assessment (HIA) with coach Joe Schmidt saying post-match he had failed and would not be available for this Saturday afternoon’s second Test against Argentina.

The 22-year-old had already suffered three concussions this year in Test matches and Super Rugby Pacific.

However, the Wallabies later issued a statement that Lynagh had passed a HIA2 test and would undergo further evaluation.

This was updated on Monday morning with the 22-year-old also passing a HIA3 test with both “presenting as normal”.

“At no point did he ever have concussion symptoms despite the result of the HIA1 being off his baseline — which could have been due to other factors at the time,” the Wallabies posted on social media.

“Tom is therefore cleared of concussion and is continuing to be monitored for the tight hamstring that forced him from the field on Saturday.”

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Lynagh made his first three starts for the Wallabies in the British and Irish Lions series in July and August but missed the Rugby Championship matches in South Africa after a high shot by Irishman Dan Sheehan in the third Lions Test.

O’Connor wore the No.10 jersey in both Tests against the Springboks before his impressive stint off the bench against Argentina.

The Wallabies’ play-making stocks are dwindling with Noah Lolesio (neck) a long-term absentee, while Ben Donaldson has been battling an adductor injury.

O’Connor will remain with the squad for Saturday’s Test at the Sydney Football Stadium but could then be forced to depart for club duties after signing with Leicester in England.

AAP