'Freak' Starc yet to hit his straps: Johnson

In worrying signs for England, the Magellan Ashes Series leading wicket-taker Mitchell Starc rates his bowling form at "five or six out of 10", according to former pace spearhead Mitchell Johnson. 

Starc has 18 wickets through five innings this summer, one wicket less than Johnson had at the same stage of the 2013-14 Ashes series in which he finished with 37 and the player of the series award.

While Johnson was firing on all cylinders four years ago, he revealed that Starc feels he's only at 50-60 per cent of his prolific potential.

"He's a freak," Johnson told cricket.com.au in Perth where he is commentating for Triple M and BT Sport. "I love watching him bowl. 

"He backs his skills. That fierce yorker he bowls is unplayable and for (him) to come out and say he's a five or six out of 10 that's pretty incredible. 

"I feel like he can definitely get better too. I'm starting to enjoy this combination (with Josh Hazlewood and Pat Cummins) as well. There's definitely that potential there. 

"But he's the leader of the attack and I just love watching how he flows in. 

"I like when he gets a bit aggro. I like when he's got a bit of a 'tache as well. I think it makes him look more angry."

Since Johnson's retirement at the WACA Ground in 2015, Starc has taken over the mantle as Australia's fastest and most lethal bowler. 

Johnson says Starc's improved consistency with the red ball is the main reason why his Test performances have gone to another level.

"He's just starting to really understand his Test game," Johnson said.

"He's always understood the one-day and T20 game, he's always dominated that. 

"Even before I retired I felt like he was starting to get it in Test cricket. It does take a little bit of time. 

"I'm just noticing that a lot more now, the consistency. 

"He's five or six out of 10 at the moment and he's got some room to improve, which is great, because you're always learning throughout your career. And even when you finish you're still learning. 

"He's a tall man, he's imposing, he bowls fast and swings the ball late. Those things are really hard to face."

Nicknamed 'Mop' for his ability to clean up the tail, Starc is a devastating threat against lower-order batsman, one that former Australia captain Ricky Ponting rates as one of the best he's ever seen.

"He's an out-and-out wicket-taker," Ponting told cricket.com.au on Friday.

"You know he's going to bowl a few full tosses and he's going to get his bouncer wrong every now and then. 

"But when he gets it right he just takes wickets. 

"It's been great to watch his development over the past four or five years. He burst onto the scene as someone who could do real damage with the white ball and there was always a bit of a worry how he could transfer that into the red-ball game. 

"He's turned into one of the best in the world. For a captain, it's nice to have that wicket-taking option up your sleeve."

Johnson says the key for Starc, 27, to maintain his wicket-taking ways is by staying fit and looking after his body.

"He definitely does all the recoveries right and jumps in the ice bath and gets that food intake and gets on the physio's bench," Johnson said. 

"You've got to do all those things right and in between games you're doing all the right things. 

"He's still in his late 20s, he's in his prime and he's just got to look after his body. 

"He's had a couple of injuries recently and he's managed them quite well. 

"He's a hard worker, he's determined, so I think all those factors come into it."

2017-18 International Fixtures

Magellan Ashes Series

Australia Test squad: Steve Smith (c), David Warner (vc), Cameron Bancroft, Usman Khawaja, Peter Handscomb, Shaun Marsh, Tim Paine (wk), Mitchell Starc, Pat Cummins, Nathan Lyon, Josh Hazlewood, Jackson Bird, Chadd Sayers.

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). Tickets

Third Test WACA Ground, December 14-18. Tickets

Fourth Test MCG, December 26-30. Tickets

Fifth Test SCG, January 4-8 (Pink Test). Tickets

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