Shane Watson is still restricted by a calf injury and is unlikely to feature in the second Test.

Australia trained at St George’s Park on Tuesday, one of two sessions the squad has at the Port Elizabeth venue before the potentially series-deciding Test starts on Thursday.

Watson batted in the nets, but instead of taking part in the main fielding session he completed some short shuttle runs under the watchful eye of team doctor Peter Brukner.

“We don’t even know much about it. He’s batting well, moving well when he’s batting, but I don’t know when his next bowl is,” paceman Peter Siddle said after the side’s first training session in Port Elizabeth. “We’ll just have to wait and see.”

When news broke of Watson’s calf issue 10 days ago, team physio Alex Kontouris suggested the plan was for the all-rounder to “be able to train unrestricted by two or three days’ out [from a Test]”.

As such, it is unlikely national selectors will have to make a tough decision on how to fit Watson in their XI until at least 1 March, when the third Test starts in Cape Town.

In the absence of Watson, Michael Clarke is likely to again throw the ball to part-time medium pacer David Warner. Warner, who is now charging in off his long run-up instead of sending down leg-breaks at training, finished with figures of 0-3 from two overs in the first Test.

“It’s been good fun working with him [Warner], he’s actually a pretty good student,” Siddle said. “He’s been in the nets working on his little off-cutters and leg-cutters. “He listens. He likes to joke around, but he’s switched on and he likes to work hard at anything he tries.

“They’re coming out alright. We’ll be looking forward to him taking that first wicket with medium pace - he’ll live off that for a very long time.”