Steven Smith was still experiencing concussion symptoms as he was ruled out of all three ODIs against England, and will need to recover fully before returning to action in the IPL for the Rajasthan Royals, whom he also captains.
Smith is supposed to land in the UAE on Thursday evening, with Royals playing their first match on September 22. ESPNcricinfo understands that the franchise remains confident Smith will be available for that game, against Chennai Super Kings in Sharjah.
A "dog thrower" short ball from the Australian team assistant coach Trent Woodhill had struck Smith on the side of the helmet in training ahead of the first ODI at Old Trafford, and though he passed initial tests, Smith showed signs of a later onset concussion in the subsequent days.
This was consistent with Smith's experience during last year's Ashes series, when he was hit on the side of the head below the helmet by Jofra Archer at Lord's and was initially cleared to return to the middle to complete his innings.
But when he felt poorly the following day, Smith was ruled out of the Test and substituted on day five by Marnus Labuschagne before also missing the Headingley Test three days later. It was not until the fourth game at Old Trafford that Smith was fit to resume.
This time around, the short limited-overs tour of the UK left much lesser time for Smith to recover, and after he struggled physically following running and net sessions ahead of the final ODI, he was ruled out by medical staff and left to only watch the decider. Australia's captain Aaron Finch described Smith as feeling "groggy" before the game, and though CA's sports science division has grown its knowledge of concussion enormously in recent years, there remains much to learn.
"Steve is making progress and working with our medical team through the concussion protocols required to return to play," CA's head of sports science Alex Kountouris said. "Unfortunately, he was not ready to play the final ODI against England. We are working collaboratively with his IPL franchise on his return to play from here once he arrives in the UAE.
"The conservative management of Steve through this injury is consistent with our approach to put the player's welfare first, as we did with him during the Ashes last year. That says a lot about the environment within our Australian teams. We are striving to create environments where players trust that our medical team will always put their welfare first and therefore speak openly with them, whether this is about concussion, other injuries or mental health.
"Cricket Australia has strict protocols when it comes to head impacts and concussions and, as we've seen over the last 12 months, we're not willing to compromise on those. We have done a lot of research over the last few years to better understand head impacts and concussions specific to cricket, and that has helped up in how we manage our players. We place the welfare of the player before the game because we strongly believe that is what's best for the player."
In the UAE, Smith's progress will be monitored by the medical staff and also the Royals' head coach Andrew McDonald, who is also Justin Langer's senior assistant with Australia when he is not fulfilling a pair of pre-existing contracts in overseas leagues.
All parties will be careful to ensure Smith is at his physical and mental best for the home summer, where he will rejoin battle against India after missing the 2018-19 series due to a CA-imposed ban for his part in the Newlands ball-tampering scandal.