India head coach Ravi Shastri said that Rohit Sharma and Ishant Sharma will have to be on the flight to Australia in the "next four or five days" if they are to take part in the Test series against Australia.Rohit is currently at the National Cricket Academy (NCA) recovering a hamstring injury and will be missing the limited overs leg of India's tour of Australia which begins on November 27."He's (Rohit) going through some tests at the NCA and they're obviously going to decide [for] how long he needs to take a break," Shastri said, speaking to ABC Sport."But things could get difficult if he's asked to wait for too long, [because] then you're talking of the quarantine again, which might make it really tough for even him to come just in time for the Test series."Shastri said that Rohit was never considered for the limited overs leg, which includes three ODIs and three T20Is before the first Test which will start on December 17 in Adelaide. A 14-day quarantine is the current norm in Australia amid Covid-19 and India are also expected to play a three-day warm-up match on December 11."He was never going to play the white-ball series, they were just looking to see how long he needed the rest, because you can't afford to be resting for too long," Shastri said. "If you need to play in the Test series or any red-ball cricket, you've got to be on the flight in the next three or four days. If you aren't, then it's going to be tough.""It's a similar case to Rohit," Shastri said of Ishant. "You don't really know how quickly he'll be available to fly out. Like I said, if anyone has to play in the Test series, he has to be on the flight in the next four or five days. Otherwise, it's very difficult."