Leeds Rhinos half-back Aidan Sezer ruled out of Grand Final and Morgan Gannon absence explained

The half-back was on the receiving end of a late, high tackle by Wigan Warriors forward John Bateman in Leeds' semi-final victory at the DW Stadium on Friday night.

Sezer has since been told that he must sit out the season decider against St Helens at Old Trafford this Saturday.

The Australian passed his off-field test but the symptoms he presented on the pitch have seen him stood down under the concussion protocols.

"I had a chat with our doctor who has been in conversation with the Super League chief medical officer and Aidan won't be available this week," said Smith.

"I believe the category one symptoms are the determining factor in terms of returning to play, whether that be in the game or the following week.

"He's shattered. The good news is he felt great going into the dressing room after he got replaced.

"He got through the post-game stuff without any symptoms or feeling bad, so that's a real positive that his health is there.

"He's clearly disappointed to be missing out but such are the protocols that are in place to take care of the welfare of our players long term."

Morgan Gannon will also sit out the Grand Final with a head injury sustained against Catalans Dragons in week one of the play-offs.

The teenage back-rower is close to completing the mandatory 11-day standing down period for a concussion but he has yet to pass all the tests and will be protected by the club.

"Morgan Gannon won't be selected this week," said Smith.

"He hasn't undergone all the protocols so wouldn't be available, but he also wouldn't be selected given he's such a young player coming off a significant situation.

"He's unavailable and wouldn't have been selected due to his age and playing the long game with that kid.

"It isn’t purely based on time. He has to be symptom-free for a period of time and he had symptoms for several days at least after the incident.

"We've made a decision as a club that we weren't going to try and accelerate any return to play given he's an 18-year-old boy with his second head knock of the season."

Wingers Ash Handley and David Fusitu'a, meanwhile, are major doubts for the Old Trafford showpiece.

"Those guys have had a run this morning but they're most unlikely to be available," said Smith, who has already confirmed that Harry Newman’s season is over.

The Rhinos will welcome at least one player back with Rhyse Martin available again after completing a two-match suspension.

The goalkicking forward was left fearing that his season may be over but the wins over Catalans and Wigan have given Martin an opportunity to play in the biggest game of the year.

"Rhyse was probably the happiest bloke at Wigan the other day given the nature of how he had to miss those couple of games," said Smith.

"It was tough for everyone to take but Rhyse handled it like a real pro. He got around the players and did everything he could to support our staff from loading the bus, unloading the bus and setting up the dressing room.

"He gave words of encouragement to the players and was very much a part of it even though he wasn't out there in the 17."