The star batsman was struck on the helmet while batting in the nets a day before the first ODI in Manchester.

Despite the 31-year-old passing multiple concussion tests in following days, Smith was ruled out of all three games.

Australia were extra cautious in protecting one of the game's greatest batsmen given the frightening blow he received from England tearaway Jofra Archer during last year's Ashes.

If the ODI series was longer, and spread further apart, Langer says Smith may have reclaimed his place in the Australian top-order.

"I think the protocols are really strict and sensible and that's how it should be," Langer told reporters on Monday.

"No one in the world loves playing cricket and batting more than Steve Smith does.

"When he didn't play the first game, I told him it's very likely that it will rule you out for the whole series because we had to play three games in five or six days.

"We're really hopeful he gets back up and running in the IPL (Indian Premier League), but we expect him to come back and be ready to play great cricket."

Smith headed straight from England, after Australia's extraordinary series-deciding triumph, to the UAE, where he will captain Rajasthan Royals in the IPL.

He took part in Royals training on Sunday and looked to be in good spirits, giving a brief interview for the team's social media accounts.

Australia's senior assistant coach Andrew McDonald is coaching the Royals and will also keep a close eye on Smith.

Rajasthan's opening game is on Wednesday against a Chennai Super Kings team containing Josh Hazlewood and former Australian all-rounder Shane Watson.

Australian Associated Press