Former Wales skipper Sam Warburton, who led the Lions to victory in Australia in 2013 and to a drawn series with New Zealand in 2017, says being captain of the party would "just suit" Itoje.
"I was so impressed with him in 2017," Warburton told BBC Sport.
"I would follow him into battle."
Alun Wyn Jones, who captained Wales to the Six Nations title and is targeting his fourth tour, is the heavy favourite to lead the Lions against the Springboks.
"Don't get me wrong, if Alun Wyn was captain I wouldn't bat an eyelid," Warburton added.