Sean O'Brien has hailed hooker Rory Best as the Ireland captain gets set to earn his 100th cap against Australia.

Best, 34, will join an illustrious list of centurions alongside Brian O'Driscoll, Paul O'Connell, Ronan O'Gara and John Hayes, when he lines out on Saturday (5.30pm, live on RTÉ Radio 1 and RTÉ2).

Speaking at the Ireland press conference, O’Brien said: “It’s going to be a special day for him.

“Rory is one of these fellas who is always thinking of the bigger picture and has always looked after the younger guys when they’ve come in, myself included.

“He’s a phenomenal player and a leader and someone you look to when you’re under pressure.

“It’s going to be a great day for him and he’ll continue to do what he’s done for us 99 times before.

“I think Rory is similar to the [previous captains] in terms of actions [speaking] louder than words.

“He’s a very disciplined player, he plays on the edge and he’s hard as well.

“He’s a good mixture of what you need in a captain and has a calm head when he needs to too, he has a lot of attributes that we look up to."

O’Brien will start his third international game in a row on Saturday after a step-by-step return to Leinster action as he gained full match-fitness following an eight-month lay-off.

Having played and impressed for the full 80 minutes in the loss to New Zealand, the Carlow man says he can still improve.

“The prep was done during the week and I had prepared myself to play a full game and I was very happy to do that and I’m glad I did,” he said.

“I think I’m a little bit off my best still.

“I think I have a lot of improvement in myself in different areas and that’s why I’m looking forward to this week, to build again on last week and see where we go from here.”

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