Meanwhile, captain Alun-Wyn Jones says he has no issues with opposite number James Horwill ahead of deciding Test in Sydney.
Gatland's head beat his heart to drop O'Driscoll from Lions squad
Warren Gatland insisted the decision to drop Ireland midfield star Brian O'Driscoll – effectively ending his British & Irish Lions career – was only difficult because it was made with the head rather than the heart.
New Zealander Gatland, who as Ireland coach first capped O'Driscoll in 1999, has preferred Welshmen Jonathan Davies and Jamie Roberts to forge the centre pairing.
While O'Driscoll's Ireland career is set to continue next term, his four-tour Lions odyssey has reached an abrupt end. When the Lions tour New Zealand in 2017, he will be 38.
Gatland, though, has never been one for sentiment, with Saturday's selection a line-up he feels can deliver a first Test series triumph since 1997 in South Africa.
Reflecting on the O'Driscoll decision, he said: "It's only hard because you are making the decision by using your head and not your heart.
"Then you realise that what comes of making a decision like that is all the peripheral stuff – not the rugby decision – because it becomes a major story for 48 hours and it becomes a debate.
"That is the process I've gone through myself. If I go back to the UK after this and say 'did I make the decision because I believe it's the right decision? or 'did I make the decision because it was the right political decision or sentiment?'
"I have to put hand on my heart and say it's the right rugby decision.
"I would hate to think we had made calls on trying to avoid criticism or public favour or perception."
O'Driscoll had been tipped by most pundits to be given the leadership duties in the injury-enforced absence of Sam Warburton, but Gatland instead opted for Wales lock Alun-Wyn Jones.
The Irishman, reportedly, offered his congratulations to the 27 year old after training in glorious sunshine at Noosa Dolphins Rugby Club on Thursday, with the squad departing for Sydney on Friday.
"He just congratulated me, simple as that," Jones said. "He is very professional in his manner and just got on with the job in training. Everyone has done the same. We haven't got a lot of time to waste now."
Asked whether he would bring his own leadership style to the pitch, Jones said: "I don't really want to change anything I just want to keep going the way I have been going on a personal level.
"I am not going to tell the backs how to kick or to pass or to run. It's a case for me to do what I've been doing with the other players in the pack and hopefully bring the win.
"You can get swept away with it [captaincy], say too much, try too hard. I've been there and done that in the past for the Ospreys.
"In the first year of captaincy there I learnt a lot, but I've had a couple of years since and it's been going well for me there, so I will just carry on with what I've been doing back at the club, essentially.
Jones has no issues with Horwill
Jones, meanwhile, says he will have no problem with his opposite number James Horwill when they line up as rival captains.
Wallabies leader Horwill plays after twice being cleared for stamping on Jones during the first Test match in Brisbane 11 days ago.
Horwill was cited for the offence, but after it was thrown out the International Rugby Board appealed that verdict, meaning a second hearing earlier this week that saw a separate judicial officer again rule in his favour.
"It's become a bit of a sideshow," said Jones, who has won 70 caps for Wales and will feature in his sixth successive Lions Test.
"I should imagine there will be some red faces somewhere for appealing the initial decision and coming up with the same decision, but that is not for me to comment on.
"I will just get on with it, and I am happy to shake his hand after the game as well."
Follow us @SprtNationalUAE