China won Team gold at Beijing 2008, and at the 2010 and 2011 World Championships, and are favourites to top the podium again.
However, Teng Haibin has been forced to pull out after tearing a muscle in his left arm during training and struggling in podium training this week.
Japan also look set to have a strong Games, with Kohei Uchimura primed to be one of the stars of the Gymnastics arena.
The reigning world All-Around champion - the only man to win three consecutive All-Around titles - won silver in the event four years ago despite falling off the pommel horse twice.
Since then he has risen to superstar status in his home country, winning his latest world title in Tokyo last year a clear three points ahead of silver medallist, Germany's Philipp Boy.
Uchimura said: 'I think that if I perform well, the result will follow me. I only think about performing to the best of my ability.'
The USA are also hot contenders and will be looking to stamp their authority on the competition.
They boast world Parallel Bars champion Danell Leyva and Olympic silver medallist Jonathan Horton in their ranks.
John Orozco, who was part of that medal-winning team, is taking a calm approach.
He said: 'I'm not putting pressure on myself or the team. I'm trying to see it as another gymnastics meet. Team is definitely more important than individual.'
It is make or break for Great Britain gymnasts Louis Smith, Daniel Purvis, Kristian Thomas, Max Whitlock and Sam Oldham in the qualification events tomorrow.
The team must finish in the top eight in order to qualify for the Team final, while individual apparatus and all-around final qualifications will also be decided.
Pommel Horse specialist Smith, who took bronze on the apparatus at Beijing 2008, said: 'There's no point risking falling off in qualification so I'll do my easier routine and I'm doing a High Bar routine beforehand as well so that will probably get me into the swing of things.'
Fans in Ireland will also be keeping their fingers crossed for Kieran Behan, who qualified for the Games as an Individual in January's test event.