Nic Maddinson's Test future hangs by a thread, while Nathan Lyon also is skating on thin ice after skipper Steve Smith refused to endorse him as a certain starter for the third Test.
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Left-arm spinner Steve O'Keefe is poised for a Test recall but Maddinson faces a nervous wait on Friday when Australia finalise their squad for what is now looming as a deciding Test in Sydney.
While selectors would love to be patient with Maddinson, who has made 27 runs in four innings, the need to provide extra cover for their battle-weary fast bowlers has to take precedence. That would pave the way for uncapped allrounder Hilton Cartwright to come into the XI at the expense of Maddinson.
![Under pressure: Nathan Lyon.](/web/20161229153206im_/http://www.smh.com.au/content/dam/images/g/t/d/q/w/1/image.related.articleLeadwide.620x349.gtjg03.png/1483007112662.jpg)
The incumbent No.6 burned a golden opportunity to consolidate his place on another rain-interrupted day of the Boxing Day Test.
While Maddinson's first two Test innings came under lights against the pink ball, and his third hit came in the pursuit of quick runs, this time the game could not have been better set up for him.
Australia had a big total on the board and he had plenty of time to make runs on a batsman-friendly track. However, he made just 22 before misreading a slider from leggie Yasir Shah and being bowled.
"He's spent a bit of time in the middle today, which is a nice thing," Smith, who strongIy advocated Maddinson's selection, said.
![Nic Maddinson walks off after being bowled by Pakistan's Yasir Shah on day four of the MCG Test.](/web/20161229153206im_/http://www.smh.com.au/content/dam/images/g/t/j/k/6/m/image.related.articleLeadwide.620x349.gtjg03.png/1483007585339.jpg)
"I'm sure he would have gained a bit of confidence out of that. He would have liked more runs, but I thought he looked pretty good today."
Smith was not as supportive of Lyon, who has taken nine wickets at 67 apiece this summer, when asked if Australia's greatest finger-spinner would be an automatic selection in Sydney.
Lyon will be named in the squad, along with O'Keefe, but it could be the latter who gets a start in the XI if selectors opt for one spinner.
"I'm not sure, that's up to the selectors. He hasn't bowled at his best this game. It's always difficult bowling to lots of right-handers. They've only got two in their line-up. They play spin pretty well," Smith said.
"It's never easy bowling to subcontinent players when the ball isn't doing a lot off the wicket as well.
"I guess we're looking for Nathan to be a bit more consistent in the way he bowls."
Like bowling coach David Saker, Smith is concerned by the workloads of Australia's quicks this series. The three-day break leading into the third Test will do little to alleviate those worries.
"They've done some bowling. It's been a pretty big summer for them as well – six Test matches is always a lot," Smith said.
"They've done some yards, which is a little concerning. They're pretty confident in their bodies that everything is going OK.
"They might not bowl much or at all tomorrow. We'll have to sum that up and see how they pull up after this Test match to see what happens in the next Test match."
Smith starred with his second century in as many games, propelling Australia to 6/465, a lead of 22, but a draw appears almost certain after the final session of the fourth day was washed out.
Only the peerless Don Bradman, India's Sunil Gavaskar and Australian Matthew Hayden have taken fewer innings than Smith's 90 to reach 17 Test centuries. Smith now has the mind-boggling average of 114.6 from his five Tests at the MCG and was not troubled by the Pakistan attack.
"For a lot of the time they weren't trying to get me out. It was about playing each ball, getting off strike, putting the bad ball to the fence. There wasn't much more to it," Smith said.