Warren Gatland says Dylan Hartley was overlooked by the British and Irish Lions for their tour to New Zealand due to the irrepressible claim of his England understudy Jamie George.
Hartley is the RBS 6 Nations champions' captain but has lost out to George, the Saracens hooker who has yet to make an international start and replaces him in the third quarter of Tests.
Also filling the position in the 41-man squad announced by Gatland are Ken Owens of Wales and Ireland's Rory Best, but it is the omission of Hartley and presence of George that has caused the biggest stir.
"We couldn't leave Jamie out. There's a potential for him to keep improving. He's done a good job coming off the bench and is playing well for Saracens," Gatland said.
"We felt there's continued improvement in him as a player and that Rory and Ken had great Six Nations.
"There was always going to be a tough call and someone was always going to be disappointed."
Meanwhile, New Zealand head coach Steve Hansen believes Hartley would have been an "asset" for the Lions.
Hansen said: "There are always going to be surprises, with some people being selected and some people not being selected.
"And that comes down to people's opinions, doesn't it? The guy that has the last say is the guy that is usually coaching them.
"I think he (Hartley) would have been an asset, but I'm not picking the team."
The Lions have not won a Test series against New Zealand since 1971 - and they have only beaten them six times in 113 years - but Hansen has no doubt about the challenge they will pose his players in June and July.
"I think this is the best British and Irish Lions team that we've seen come here for a long, long time," he added.
"There is depth all the way through. That's why people like Hartley and some of the Scottish boys have missed out because there is so much depth.
"You've only got to look at the five-eighths (fly-halves). A guy like Finn Russell has been playing really well and can't even make the team because they've got (Jonathan) Sexton, (Owen) Farrell and (Dan) Biggar there. You have also got young (George) Ford missing out.
"There is a lot of depth right through all the positions. The locks are the same, the loosies (back-row forwards) are the same.
"It is going to be a very good side, and they will come with a lot of expectation, which I think is going to be interesting to see how they cope with that - a lot more expectation than they've been used to, because people expect them to win.
"(The squad) is pretty much what you would expect from Warren.
"He likes his big ball-carriers in the middle of the park and his big, grunty forwards, so that is what he has picked, and I would expect that we are going to get a similar game style to what we've always got whenever we have played a Warren Gatland team."
Hansen is due to name a 33-man All Blacks squad for the Test series on June 8, by which time the Lions will have already played two games during a tough first Test build-up that features appointments with Super Rugby sides the Blues, Crusaders, Highlanders and Chiefs, plus the Maori All Blacks.
"Our job is to make sure we keep a good eye on what they do in the games they play prior to us and try and get a read," Hansen said.
"We have to get on with our job, make sure our game is as good as it can be as soon as it can be, and make sure that we've got as much covered as we possibly can.
"There are a number of people who are playing very, very well who haven't been All Blacks, and there are a number of All Blacks who are playing well."