Lyon is set to surpass Dennis Lillee's 355 Test wickets, with only Shane Warne (708) and Glenn McGrath (563) ahead on the all-time Australian list.

The off-spinner - nicknamed the GOAT among teammates since he surpassed Hugh Trumble's 141 wickets in 2015 - is likely to pass Lillee's haul during the third Ashes Test at Headingley Cricket Ground.

Australia head to Leeds with a 1-0 Ashes series lead and Lyon's 355 Test scalps have the former ACT Comets skipper in league with the game's greats.

Lyon, who has 88 Test caps, has seemingly flown under-the-radar and is often understated despite numbers saying he's a modern great.

Even he didn't realise he joined the legendary paceman as Australia's third-highest Test wicket-taker until he walked off the pitch at Lord's.

"He has an interesting and almost unidentifiable method of going under the radar with almost every game he's played," Lawson said.

"He's never spoken as one of the main bowlers of the series like a Lillee, McGrath or Warne and I'm not sure why that happens because the record speaks for itself.

"He continually performs and he never lets anyone down yet he seems to be underrated."

Lyon has taken more wickets than any Test bowler in the world since he debuted against Sri Lanka in 2011.

Lawson believes the 31-year-old finger-spinner could have another ten-years left in the tank and therefore overtake Warne as Australia's all-time wicket-taker.

"He might not just be the 'GOAT' for off-spinning but could become the greatest of all Australian bowlers," Lawson said.

"The future could go on for ten more years and he may well end up around the 700-wicket or more mark.

"However he does that, he'll still be the same Nathan Lyon doing his job, contributing to his team, loving the game, and turning up to practice."

Lyon, an improbable hero, has become Australia's go-to man on the fifth day, much like he was for Paine in the Ashes opener.

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All eyes were of Steve Smith during the first Test but it was Lyon who bowled Australia to victory with a six-wicket haul at Edgbaston.

Lawson said Lyon's legacy will likely mirror his 'understated' career but hopes it'll encourage and set the benchmark for young off-spinners.

"Warne set a legacy for the leg spinners which probably hasn't quite been realised, and lots of fast bowlers - like McGrath, Lillee or Thompson - always set benchmarks and goals for young kids to be that style of bowler," Lawson said.

"Not many people say 'I want to be an off-spinner' but maybe Nathan Lyon will encourage those.

"He does it very simply. He's not complicated in the way he goes about his job and like his cricket, it'll be an understated legacy and a quiet achievement which is a nice thing to have.

"Warne was a very loud achiever, the way he went about his game and his off field. Lyon is quite the opposite but they're both incredibly important cricketers."

Meanwhile Steve Smith has been ruled out of the third Ashes Test at Leeds following a delayed concussion inflicted by a Jofra Archer bouncer.

Smith, who has contributed nearly a third of Australia's total runs so far this series, was struck on the neck while batting at Lord's and failed medical assessment for the upcoming match.

Lawson said Smith's absence will be a major blow for Justin Langer's side, who are one win away from retaining the Ashes.

"It's not just runs that are obvious from him, it's the ring of confidence he takes on the field and teammates knowing they have Steve Smith on their side," Lawson said.

"They've got to battle the physical loss of run making but also the mental loss of losing their best batsman."

Marnus Labuschagne, having delivered a matching-saving 59 at Lord's, is set to replace Smith again at Leeds.

He's expected to slot straight into bat at No.4 but Lawson said every player needs to contribute to fill Smith's void.

"David Warner is due for some runs and we know he's capable," Lawson said.

"They need some good opening partnerships and neither side had that in the two Tests, the bowlers have really dominated.

"If either side gets a good opening partnership it'll be the way to a good start, but everyone has to contribute to a certain degree.

"If Marnus Labuschagne comes in then he's going to make up some runs but it's not just one player making up the snippets. It's everyone playing their game to make that difference."

AUSTRALIA'S LEAD TEST WICKET TAKERS