The British and Irish Lions coach Warren Gatland said the decision to drop Brian O'Driscoll was "not easy" but claimed the Irishman's leadership would still be vital for the touring side in the run-up to the Sydney showdown.
Gatland said "the head overruled the heart" when it came to selecting the squad that will face Australia in the decisive third test match.
When asked how O'Driscoll took the news, the Lions coach said: "I told him this morning. Obviously he was pretty disappointed as anyone is disappointed but he appreciated the fact that he was spoken to before the announcement.
"It's the first time any coach has ever had that decision with him in 15 years of rugby so it's not easy for that to be the first time but he's still going to be very important for us for the next 72 hours".
The British and Irish Lions coach Warren Gatland said the "head overruled the heart" on many of his selection decisions for the final test against Australia in Sydney.
Former Lions captain Brian O'Driscoll said he was "totally gutted" at being left out of the squad for the decisive match this Saturday.
Gatland said: "Picking this team was not easy and ultimately with several players available after recovering from injury the head overruled the heart in many selection decisions.
"Brian O'Driscoll is a great player and has had a wonderful career but for the final test in Sydney, we just felt Jamie Roberts' presence offered us something more".
Former Australian Rugby Union legend David Campese and current player Matt Giteau have criticised the British and Irish Lions' decision to drop Brian O'Driscoll.
Lions team info. Sorry but you have just handed to series to Australia. 7 chances and still no real match winner
Gee dropping @brianodriscoll out of the team is a huge call.. For mine, he has been the stand out unsung hero this series.. Defensively huge
However, former England player Jeremy Guscott praised Warren Gatland's "bold and brave selection".
Well done WG, bold and brave selection that was required to beat this improving Aussie team
Former Lions captain Brian O'Driscoll has said he is "totally gutted" at being left out of the squad for the final and decisive Test against Australia:
Obviously totally gutted at being left out for deciding Test but all efforts go into preparing the boys to see it through. #seaofred
@giteau_rugby cheers man, hard one to take.