Lions coach Warren Gatland has used a trip back to Ireland to explain how difficult it was to drop local legend Brian O’Driscoll for the final test on the victorious tour to Australia in June.

The Welsh boss, who also coached O’Driscoll during his time in charge of Ireland, picked a healthy Jamie Roberts ahead of Dricco for the final test.

Gatland told RTE’s 'Late Late Show,' “It’s the toughest thing I’ve had to do in my coaching career.

“It was incredibly tough. And the thing about it is particularly someone like Brian, who has been a legend in the game — I gave him his first cap at 19 — and to be the first person to drop him in his rugby career was tough.

“Hand on my heart, sitting around as coaches to pick the side for the third test, we felt we picked a team that would go out and do a job.

“The mandate that I was given by the Lions board was do whatever it takes to win a test series in Australia, and the Lions hadn’t won for 16 years, and previously there had only ever been three successful Lions tours ever.

“Sometimes you’ve got to make decisions that aren’t always the most popular. I knew there was going to be a fallout, but I didn’t realize how big.”

Asked to explain why he dropped O’Driscoll for Roberts, Gatland added, “Well, I think Jamie Roberts had come back from injury, so it meant having him available for the combination of Jamie and Jonathan in midfield.

“Nothing against Brian’s performance in the first and the second test.

“As a coach, when you go and talk to players and give them bad news, it’s the hardest thing about coaching and it’s always difficult to do.

“But at the end of the day selection is just a matter of opinion, and that’s all it was, just a matter of opinion.

“It was such a tough call to make. Hand on my heart I felt, and I’ve got to believe, that we made the right decision, but that doesn’t mean that I don’t respect other people for disagreeing with the selection that we made.

“I took no pleasure out of it. It was difficult afterwards to enjoy the result and it took a bit of time because it was such a tough call to make.”