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* Gatland to lead Lions to South Africa in 2021
* New Zealander standing down as Wales coach after World Cup
* Lions lost last series against Springboks in 2009
By Mitch Phillips
LONDON, June 12 (Reuters) - New Zealander Warren Gatland will lead the British and Irish Lions for the third time after being named on Wednesday as head coach for the 2021 tour of South Africa.
Gatland, who led the Lions to a series victory over Australia in 2013 and a drawn series against New Zealand in 2017, was widely expected to be given the role despite saying two years ago that he was "done" with the job and that it was time for someone else.
He was an assistant to Ian McGeechan when the Lions last toured South Africa, losing the 2009 series 2-1. They won their previous series there, also under McGeechan, in 1997.
Gatland, 55, will stand down as Wales coach after this year's Rugby World Cup in Japan having become the country's longest-serving coach and leading them to three Grand Slams. Wales won the Six Nations championship earlier this year.
For his previous two stints as Lions boss Gatland took a sabbatical from his Wales duties but is now clear to dedicate himself entirely to the combined team and will take up his duties in August 2020.
He will face the usual challenge of trying to blend a squad and team from the four contributing countries - England, Wales, Scotland and Ireland - with limited time.
"I'm hugely honoured and delighted to lead the Lions again," Gatland said at the announcement at a London hotel. "The Lions rightly have a truly special place in the game and I jumped at the chance to be involved again.
"South Africa is a special place to play rugby. They have some of the most iconic stadiums in the world which will be packed full and the Springboks have shown in recent times that they are back to being one of the dominant forces in the game.
"Having toured there in 2009 I know the scale of the task ahead of us. Playing in South Africa presents a number of unique challenges, such as playing at altitude, while the Boks will always be physical, aggressive and highly motivated."
After the New Zealand tour, Gatland said that the squeeze on preparation time was putting the whole Lions concept at risk but the 2021 tour looks set to be even tighter.
No official dates have yet been released but the tour is expected to last five weeks, featuring eight matches, down from six weeks and 10 games in 2017.
It is also likely to run from July into August - the latest in the year of any Lions tour - following changes to the international calendar that take the European domestic seasons through to late June and give him only three weeks with the players before the first tour game.
"I'm delighted to have everything in place to begin full time in August 2020 as that gives me the best possible chance to plan," Gatland added.
Lions chairman Jason Leonard, who played on the victorious 1997 tour, said: "One of Warren's greatest strengths is the ability to galvanise a group quickly and the last two Lions tours have shown that Warren understands and truly loves the Lions."
Tens of thousands of fans are likely to travel to South Africa as Lions tours have developed into a huge pilgrimage over the last 20 years or so, red-clad fans usually outnumbering home fans. Leonard said that support was vital and much appreciated.
"We may be playing away in the heartland of South Africa but I am confident that yet again we will have enormous support and they will feel like home games," he said.
"As a player it made all the difference and now I can't wait to be part of the famous sea of red enjoying the tour of a lifetime." (Reporting by Mitch Phillips, editing by Christian Radnedge)