Dropped centre Brian O'Driscoll conceded it was a "bittersweet" moment as he watched the British and Irish Lions seal their first series victory for 16 years.
Writing in the Daily Telegraph, O'Driscoll said: "The final whistle was bittersweet. You do not feel as much part of it if you have not played, no matter what. That is just how it is."
He added: "It was a massive mix of emotions: delight at being part of this historic moment alongside guys you have battled with, but tempered by not playing. It was hard and I would be lying if I said otherwise.
"You are desperately envious of those who are out there but there is not a sliver of ambiguity about wanting to see the boys win. That is non-negotiable: 100 per cent you want the team to go well. I have spent a lot of time with these guys.
"But thanks be to God, I am a series winner with the British and Irish Lions, albeit it did not finish as I would have liked it to. But you cannot write your own script."
O'Driscoll relived the moment on Wednesday when he was dropped for the first time as a professional.
The Irishman had widely been tipped to be named captain in what would have been his final Test for the Lions, but he knew the writing was on the wall when Gatland and assistant coach Rob Howley approached him by the coffee machine and asked for a quiet word.
"I realised a quiet word in the meeting room was not a good sign," he said. "They were not going to ask me to be captain. That would have been said to me there and then. It was a blow.
"Having seen other players react in the past to being dropped has given me an insight into how to respond and behave properly. I have seen guys who are dead men walking on tours when they have not been selected and you cannot be that person."