The contrasting fortunes of dueling off-spinners Nathan Lyon and Moeen Ali has been one of the major differences in the Magellan Ashes Series, says Test great Mike Hussey.
As Australia march towards a four-nil series victory that will see the iconic urn return to Australia, Lyon has been the lynchpin for Steve Smith's high-octane bowling arsenal.
The four-pronged attack of Lyon, Mitchell Starc, Josh Hazlewood and Pat Cummins are only the third quartet in the history of Test cricket to each take 20 or more wickets in a series, behind the West Indies in 1995 and 2006-07 Australian team that whitewashed England.
And of the four, Lyon has been the most economical while picking up vital wickets during the series – most of which have been left-handed.
"It's been crucial for Australia's chances of winning the Ashes for Nathan Lyon to bowl well," Hussey told cricket.com.au.
"He's had some left-handers to bowl to … that's been important to him, he bowls very well to left-handers.
"But it's been important that he's bowled well and bowled long spells because that's enabled Steve Smith to rotate the fast bowlers from the other end and keep them fresh, particularly aggressive-type bowlers like Mitchell Starc."
Lyon has bowled the most overs in the series with control, patience and discipline – the opposite of what Moeen has been able to offer Joe Root and England.
There was perhaps no better example of the gulf in class between Lyon and Moeen than the Australian's dismissal of Alastair Cook.
For 48 overs on a turning Sydney Cricket Ground pitch, Moeen toiled away to finish with two wickets – the first a shock return catch off Steve Smith, the second Mitchell Starc, who skied a slog sweep having hit the previous ball 20 rows into the stands for six.
While Moeen needed 288 balls to remove two batsmen, it took Lyon only five deliveries to castle Cook, who was beaten all ends up with a flatter ball that spun sharply and clipped off-stump.
Lyon has dismissed Cook eight times in Test cricket, more than any other batsman, and his ability to remove key players is why the off-spinner is just 11 wickets away from the 300 mark.
In contrast to Lyon's 20 wickets, Moeen will likely finish the series with five wickets at an average of 115 runs apiece, the highest average of any bowler in a series having taken five or more wickets.
England blooded Mason Crane for the fifth Test, the leg-spinner who recorded the fifth-most expensive figures on debut in Test match history, and Hussey says playing a specialist spinner might make Moeen more relaxed in the role.
"You look at the quality of Nathan Lyon and the Australian spin bowling compared to England with Moeen Ali - he's really found it tough," Hussey said.
"It's not easy for finger spinners to do well in Australia.
"He's a different bowler to Nathan Lyon and his confidence hasn't quite been there.
"He's bowled to try and keep it tight whereas Nathan Lyon, you can tell he's attacking, looking for wickets.
"Maybe there's a difference in mindset there, but there's also a difference in class.
"I personally see Moeen Ali as a batsman who can help out with the ball and perhaps having a second spinner there may have taken the pressure off him."
England assistant coach Paul Farbrace said after play on day four that Lyon has been just as influential as Smith this series.
"I think he's had a fantastic effect on this series and he really has been … there were times when you talk about on flat pitches let's make sure we get the seamers into second, third, fourth spells, he has been able to come on and bowl long spells.
"Right back to Brisbane, that surface probably surprised all of us with the way that it played, he bowled brilliantly from there and almost in a way we've not got away from his stranglehold.
"He bowled very well to start well there, we've found him hard to rotate against and he's gone on to have a massive effect on this series.
"Along with Steven Smith has been their star performer in that he's allowed their seamers to have decent periods of rest and he's always been a threat and he's always taken important wickets throughout the series, which is testimony to his high-level of skill."
2017-18 International Fixtures
Magellan Ashes Series
Australia Test squad: Steve Smith (c), David Warner (vc), Ashton Agar, Cameron Bancroft, Usman Khawaja, Peter Handscomb, Shaun Marsh, Mitchell Marsh, Tim Paine (wk), Mitchell Starc, Pat Cummins, Nathan Lyon, Josh Hazlewood, Jackson Bird.
England Test squad: Joe Root (c), James Anderson (vc), Moeen Ali, Jonny Bairstow, Jake Ball, Gary Ballance, Stuart Broad, Alastair Cook, Mason Crane, Tom Curran, Ben Foakes, Dawid Malan, Craig Overton, Ben Stokes, Mark Stoneman, James Vince, Chris Woakes.
First Test Australia won by 10 wickets. Scorecard
Second Test Australia won by 120 runs (Day-Night). Scorecard
Third Test Australia won by an innings and 41 runs. Scorecard
Fourth Test Match drawn. Tickets
Fifth Test SCG, January 4-8 (Pink Test). Scorecard
Gillette ODI Series v England
First ODI MCG, January 14. Tickets
Second ODI Gabba, January 19. Tickets
Third ODI SCG, January 21. Tickets
Fourth ODI Adelaide Oval, January 26. Tickets
Fifth ODI Perth Stadium, January 28. Tickets
Prime Minister's XI
PM's XI v England Manuka Oval, February 2. Tickets
Gillette T20 trans-Tasman Tri-Series
First T20I Australia v NZ, SCG, February 3. Tickets
Second T20I – Australia v England, Blundstone Arena, February 7. Tickets
Third T20I – Australia v England, MCG, February 10. Tickets
Fourth T20I – NZ v England, Wellington, February 14
Fifth T20I – NZ v Australia, Eden Park, February 16
Sixth T20I – NZ v England, Seddon Park, February 18
Final – TBC, Eden Park, February 21