Ireland flanker Chris Henry believes there are four players in with a shout of captaining Joe Schmidt's squad.
The Ulster forward, speaking ahead of the Samoa fixture, said the fight is between Paul O'Connell, Brian O'Driscoll, Jamie Heaslip and Rory Best.
"We as players don't really know who the captain is yet," revealed the eight-cap back-row forward, speaking to Press Association Sport.
"But look around: there are options all over the place and Paul (O'Connell) definitely is up there.
"There's a lot of inspirational characters there. I suppose sometimes when I'm running around training, you look at the circle of players and you still have to take a second glance sometimes, with Paulie, Drico and Jamie, and Rory as well.
"Whoever gets the nod will be extremely proud of course but there are options all over the place, and the fact that we have so many leaders, whoever gets the nod will have a lot of experienced hands behind him as well.
"I'm glad I don't have to make the decision, but in my head the four candidates would be Paul, Drico, Jamie and Rory.
"Any one of those boys will do exactly the right job and we'd all stick behind them exactly the way it should be."