Allrounder Mitchell Marsh is in doubt for his Test debut later this month after a hamstring injury ruled him out of Australia's T20 against Pakistan this Sunday. Marsh is also unlikely to play in the three-match ODI series that follows the T20 after he picked up the hamstring injury while playing for Perth Scorchers in the Champions League T20.

Marsh appeared a near-certainty to make his Test debut in Dubai in the absence of injured allrounder Shane Watson, and if he is unavailable it could bring offspinning allrounder Glenn Maxwell into the mix. The heat in the UAE will mean Australia need an allrounder capable of bowling a significant number of overs, and Marsh may need to prove his fitness in the four-day tour game against Pakistan A.

"He's not playing the T20 and he's unlikely to be okay for the one-dayers," Kountouris said. "The timelines are just too tight and we're probably not going to have a crack at it I don't think. He's moving around okay and seems okay, but we'll wait and see for the Test matches how he progresses. There's certainly enough time for the Test matches."

Marsh had undergone surgery on the same hamstring - on his left leg - two years ago. According to Cricket Australia, he had "felt a pinch" in his hamstring while captaining the Scorchers against Lahore Lions on Tuesday and went off the field for an extended period, but had later come out to bat, bailing the team out from a tight corner with 63 not out off 38.

However, the injury apparently worsened on the flight to over to Dubai. Scans revealed that he had possibly torn scar tissue from the previous injury, but Cricket Australia is seeking the opinion of specialists, including the surgeon who had operated on him two years ago.

"Trying to decipher what's new, what's old, what's abnormal, what's normal, is a bit hard," Kountouris said. "So we're getting some opinions from back home from the guy who did the surgery, just to double-check with what we're doing. The consensus is that he's only torn the scar tissue but we're still looking into it.

"If that's the only thing that's happened it's going to be a sort of mild hamstring strain. It might get better really quickly or it might get better very slowly. That's what we don't know because of the unique nature of the injury."

The two-Test series begins on October 22 and should Marsh play he will join his brother Shaun and father Geoff as Australia Test representatives. The four-day warm-up game in Sharjah is likely now to effectively serve as a fitness Test for Marsh as well as captain Michael Clarke, who is also recovering from a hamstring problem.