Twelve years after making his British & Irish Lions debut Down Under, O'Driscoll is about to embark on a fourth tour.
And Eales, who led the Wallabies to their series victory in 2001, insists the Ireland veteran is still the centre of attention.
"The Lions always pick a mixture of youth and experience and there will be some guys who have been there and done that many times before; O'Driscoll is one of those guys," said Eales.
"He's going to be very important, not only from a playing perspective. He more than holds his own as a player, but also very much from a leadership perspective and being able to bind that team together.
"He will pass on the lessons of where they fell down in Australia in 2001, so they can be a more potent force back here this year."
Eales knows all about facing the Lions and he reckons the six match build-up towards the first Test will be a major benefit to the tourists.
"I've only been on the other side of the fence, but I could imagine one of the most exciting things about a Lions Tour is actually being part of that bonding," said Eales.
"When they get together in a few weeks' time and they have that first game in Hong Kong against the Barbarians and then land in Perth, it's about putting a team of players together that are used to playing against each other and developing those common bonds.
"It's not an easy thing because they're used to having this passion against each other, but if you get it right it can be a very powerful motivating force for the team and they'll be doing everything they can to get that right."
In 2001, Eales went head to head with Lions captain Martin Johnson. Sam Warburton has been handed the honour for the latest tour Down Under and the Wallabies legend can understand why.
"Warburton had success leading Wales and he is seen as a guy who is very composed," said Eales.
"People look up to him, he gets the best out of his players, he's a forthright guy who seems to have an impact on the style of play the team has and he shows a lot of confidence in his players. He is seen as someone who relates well to referees, relates well to his own team and he certainly doesn't take a backwards step.
"Gatland, who's a bright coach and had success at many different levels, is going to be thinking who is going to be the best captain to pull this team together to have an impact against Australia this time. He would have given that long consideration."