Robbie Henshaw and Johnny Sexton have been ruled out of Ireland's fourth and final match of the Autumn Series against Australia on Saturday.

Sexton suffered a hamstring injury (not a reoccurrence of the old one), while Henshaw was knocked unconscious by a shoulder contact to his jaw. As a reasult, the Irish centre suffered concussion and will not be available this weekend.

"The evidence is fairly clear that Robbie took a shoulder to the jaw, which knocked him unconscious," said Irish manager Mick Kearney. "Robbie was pretty much unconscious before he hit the ground. He was back in the dressing room very groggy, very sore still. He came in this morning to see the doctor and has since returned home."

Backrow CJ Stander was also removed from the game with suspected concussion and will complete the Head Injury Assessment process and Return To Play (RTP) protocols, while fullback Rob Kearney will also follow RTP protocols after suffering concussive symptoms post-game.

Despite going down after being caught by a high tackle, Simon Zebo has only suffered from cramp, which occurred in the last 10 minutes. He is expected to train later on in the week.

Peter O'Mahony, Keith Earls and Ultan Dillane are expected to return to training this week also.

“We don’t think it’s too bad. It’ll certainly keep him out this weekend, but the expectation is that it may not be much longer than that,” said Irish manager Mick Kearney on Sexton. “One to two weeks maybe.”

If Stander and Rob Kearney are able to train by Thursday they will be available for selection against Australia.

“It was very quiet day today, to be honest,” added the Irish manager. “The lads all came in last night, very tired and sore after a physical battle. So today they just went through a few meetings and then did a walk-through.”