Two of Australia's greatest fast bowlers have questioned the form, match fitness and body language of Test spearhead Mitchell Starc.
As the hosts fought to stay in the series opener in Adelaide, Starc took the second new ball and struggled to find his line and length, swinging two balls wildly down leg side for four byes apiece and costing Australia 17 runs from two overs before he was taken out of the attack.
In commentary during that period, pace-bowling legend Glenn McGrath discussed a lack of rhythm due to a potential technical issue in his run-up.
"At the moment he just doesn't seem to have that rhythm," McGrath said on Seven. "If you've got good rhythm in your run-up, good intent running in and building up pace … a strong front arm and getting through the crease (you're likely to be bowling well).
"I just think it's got to do with his run-up firstly, and then when he gets to the crease he doesn't have his normal rhythm. He's probably leaning back a little and overstriding, and then you don't get through the crease as well.
"We saw two balls where (he) dragged it down the leg side (and) went for four byes. You know when you (don't have) rhythm, it's coming out poorly.
"He's not using his run-up, he's trying to do it all at the crease.
"And you've got to feel for him – when the confidence is down, you've just got to relax and trust in yourself that you haven't forgotten how to bowl overnight.
"Just run in, relax and just bowl."
Ahead of the ongoing Domain Test Series opener, Starc alluded to changes in his action in recent times that had been caused by an attempt to push through minor injuries or soreness during spells, which he discussed with Australia fast bowling coach David Saker.
"We had a bit of a chat a few months ago now prior to the UAE tour about how my action had probably changed, bowling through niggles and periods where I'd been sore and that sort of stuff," he said in Adelaide. "There were times when I'd collapse on my knee to try to get through when I was sore and that sort of thing.
"Just little changes and little cues I used to have that I probably went away from – or unknowingly went away from."
During a crucial phase in the Test on the afternoon of day three, Starc spent more than two hours out of the attack, despite producing the tidy figures of 1-18 from 10 overs by stumps.
After play on Saturday he spent time with Adelaide Oval ground staff in an attempt to get them to fix foot holes at the popping crease that had been troubling him. Starc said on Fox Cricket his previous ankle injuries had him concerned about the footholes.
Mitchell Johnson, who played 13 Tests alongside Starc during his 73-match career, suggested the 28-year-old had failed to "let the batsman know he's in the contest" while speaking during commentary on Sunday.
"I just don't like his body language," Johnson said on ABC Grandstand today. "He hasn't given a bit of a glare or puffed his chest out with a good follow through, let the batsman know he's in the contest, that he's going to rip the pegs out."
Following his two-over second-innings stint with the new ball, Starc had taken 10 wickets at an average of 57.80 from his previous five Tests. The left-arm quick struck in just his fourth over on day one in Adelaide, and went on to claim first-innings figures of 2-63 from 19 overs. He finished with 3-40 in the second innings to improve his bowling average from his past five Tests to 48.66. McGrath suggested fatigue and a lack of match fitness was potentially an issue.
"Watching him bowl in the first innings, I was happy with the way he was going," McGrath added. "He was swinging the new ball, he was bowling good areas.
"But whether he hasn't had enough bowling under his belt – they bowled 19-20 overs in that first innings, he's bowled quite a few in this second innings – whether he has the bowling fitness to get through the matches (I'm not sure).
"That's why I always worry about resting players … you do need the bowling under the belt. Match fitness – you can't get it in the nets, you can't get it running, you can only get it out there in the middle."
Australia spin legend Shane Warne also picked up on the match-fitness of Starc, and said his returns in 2018 were "not good enough".
"He's the leader of the attack, your main strike weapon, he cleans up the tail really well, but to take 19 wickets at 36.1 in six matches, he probably needs to be better than that," Warne said on Fox Cricket.
"It's not good enough, if it's not working, and you're having too much time off, you've got to find a way to play more cricket to find your rhythm."
Australia bowling coach Saker said while there were some issues with ensuring the left-armer was finding his line and length, he had found "good rhythm and some good pace" during the Test.
"He was OK yesterday I thought," Saker told ABC Grandstand. "First innings he was particularly good as well but he missed (the mark) obviously with that second new ball, wasn't as good as he could have been.
"I think he's bowling with some really good rhythm and some good pace, it's just a matter of getting the ball in the right area as much as he possibly can.
"We'll explore him going around the wicket this morning (of day four) a little bit more, it makes it easier for him to control where the ball is going.
"I've been really happy with how all the three quicks are going, and Nathan (Lyon)."
Test legend Allan Border had a contrary view to Saker, suspecting something was amiss with the 28-year-old quick.
"I disagree (with Saker), it just looks like he's off his absolute best, particularly when bowling over the wicket," Border said on ABC Grandstand. "He just doesn't seem to have the same rhythm.
"There's something not quite right there. When he goes around the wicket he's got better rhythm and his lines are better."
Domain Test Series v India
Dec 6-10: First Test, Adelaide Oval
Dec 14-18: Second Test, Perth Stadium
Dec 26-30: Third Test, MCG
Jan 3-7: Fourth Test, SCG
Australia squad: Tim Paine (c, wk), Josh Hazlewood (vc), Mitch Marsh (vc), Pat Cummins, Aaron Finch, Peter Handscomb, Marcus Harris, Travis Head, Usman Khawaja, Nathan Lyon, Shaun Marsh, Peter Siddle, Mitchell Starc, Chris Tremain
India squad: Virat Kohli (c), Murali Vijay, KL Rahul, Prithvi Shaw, Cheteshwar Pujara, Ajinkya Rahane, Hanuma Vihari, Rohit Sharma, Rishabh Pant (wk), Parthiv Patel (wk), Ravi Ashwin, Ravi Jadeja, Kuldeep Yadav, Mohammed Shami, Ishant Sharma, Umesh Yadav, Jasprit Bumrah, Bhuvneshwar Kumar