The secrecy surrounding NSW's Origin line-up was almost blown when Brisbane media unknowingly crashed a training session in Brisbane this morning.

Coach Ricky Stuart has still not named his final line-up for tomorrow night's series decider, and several names are still in doubt.

He has been training the team away from the public spotlight, but this morning's session was interrupted as press attended a press conference with James Horwill of the Queensland Reds at the same time.

The Reds are set to play in the Super Rugby final against the Crusaders this weekend.

NSW officials had been unaware of the clash and there was a desperate scramble to keep NSW team members away from members of the media.