South Australia paceman Chadd Sayers could be in line for a return to Australia's Test squad should Jackson Bird not pull up fit ahead of Thursday's departure to South Africa for the upcoming four-Test tour, head coach Darren Lehmann confirmed today.

Bird injured his hamstring on Saturday, during Tasmania's Sheffield Shield clash with Queensland in Brisbane, leaving the field immediately after pulling up sore from a delivery.

Bird forced from field with hamstring strain

He underwent two inconclusive scans and was due to again be assessed today in Melbourne, with his position as one of five fast bowlers for the tour to South Africa now in considerable doubt.

After a strong start to the Shield summer, Bird played the fourth Test of the Ashes in Melbourne in the absence of the injured Mitchell Starc, and again loomed as the likely replacement for headline trio Starc, Josh Hazlewood and Pat Cummins in South Africa.

However his untimely injury could open the door for Sayers, who has taken more Shield wickets than anyone over the past 18 months – including a record-breaking 60-wicket season in 2016-17.

Despite consistently being on the fringes, Sayers is yet to win a Baggy Green cap.

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"Jackson's being assessed by the medical staff today so we'll make a call on that in the next 24 hours and see how he goes," Lehmann told cricket.com.au today.

"We'll replace him if required. The logical (replacement) is probably Chadd Sayers, but we'll sit as a selection panel and work that out.

"We'd like a fully fit squad to go into a tough tour. So if he is to tour, we want him playing the tour game."

Lehmann's desire for Bird to play the tour match shortens his window of recovery by a week; the first Test begins on March 1, however the slated three-day practice match in Benoni is due to begin in 10 days' time, on February 22.

Sayers returned match figures of 0-135 from 42 overs in the Redbacks' loss to Victoria, which concluded yesterday, but has been regularly discussed as a potential Test bowler.

Last month, the 30-year-old reacted with surprise at the selection of WA youngster Jhye Richardson for the tour of South Africa.

"I guess that's one of the disappointing things, that I haven’t had a phone call to actually find out why I was left out," he told 5AA. "It would be nice to know.

"I found out on social media so I guess that's one of the disappointing things.

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"Not being in the touring party and being dropped from the squad, I was involved in the Ashes, was also disappointing but not to have had a chance to find out why is hard to take.

"I have tried to call (chairman of selectors Trevor Hohns).

"Hopefully he gets back to me tonight and I can have a chat to him and can get some clarity on how Jhye Richardson, who has only played five Shield games, was picked ahead of me.

"I'd like to know where I stand in Cricket Australia's eyes and where I can get in their side. It's quite hard to take at the moment.

"I'm just disappointed and just want some clarity."

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Speaking after the squad was announced, Hohns praised Sayers for his recent form but added the selections of Hazlewood and Bird meant the squad was well-stocked with swing and seam bowlers of a similar ilk to the Redbacks right-armer, essentially suggesting the selection was a matter of balance.

And he added youngster Richardson, one of the quickest bowlers in the domestic scene, would "benefit immensely" from his first Test tour.

"Chadd is performing well, as he always does, but with Jackson Bird there he has the jump on Chadd at the moment, there's no doubt about that," Hohns said.

"We have him, Josh Hazlewood is a well-renowned seam bowler, then we have the good pace of Starc, Cummins and Jhye Richardson."

Qantas tour of South Africa

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

Warm-up match v SA Invitational XI, Sahara Park, Benoni, Feb 22-24

First Test Kingsmead, Durban, March 1-5

Second Test St George's Park, Port Elizabeth, March 9-13

Third Test Newlands, Cape Town, March 22-26

Fourth Test Wanderers, Johannesburg, March 30-April 3