Time is running out for Warren Gatland to settle on the squad he will take to New Zealand in June in the hope of securing a second series win as British and Irish Lions head coach.
Gatland oversaw a 2-1 win in Australia four years ago but does not have history on his side when it comes to the All Blacks, with the Lions having not won a series in the Wales coach's homeland since 1971.
Here we take a look at the biggest calls Gatland will have toiled over in recent months, and some that may still be giving him a headache as decision day looms.
No decision commands more attention than this one, but Gatland has frequently played down the significance of the role, stressing whoever is chosen will not necessarily be a guaranteed Test starter.
Sam Warburton is favourite for a return to the role he occupied in 2013, although injury and his decision to relinquish the Wales captaincy could have a bearing on Gatland's decision.
Current Wales skipper Alun Wyn Jones is also in contention, but Ireland's Rory Best will tick a lot of boxes when Gatland weighs up his options.
Best is the only man to captain a side to victory over the All Blacks since August 2015 and he inspired Ireland to a spirited victory over England in the final round of the Six Nations.
England skipper Dylan Hartley is not certain of a place in the squad, so his chances of being handed the captaincy appear slim, while Best's compatriot Conor Murray is fancied by some.
Gatland has already commented that "some quality players will miss out on selection" in the second and back rows, and it is an area of great depth for the Lions.
Warburton impressed during the Six Nations and could be joined by international team-mates Justin Tipuric, Taulupe Faletau and Ross Moriarty, while Ireland will expect to be strongly represented.
Jamie Heaslip, CJ Stander, Sean O'Brien and Peter O'Mahony are all in the mix and that's before even considering any English or Scottish options.
A fully fit Billy Vunipola will be expected to start the first Test at number eight, while England colleagues Chris Robshaw and James Haskell will also hope to be involved, and Scotland's Hamish Watson will be hoping for a spot.
The interesting thing about the decision facing Gatland at 10 is that he could be spoiled for kicking options throughout the backs, depending on the selections he makes in other positions.
Stuart Hogg, Leigh Halfpenny, Elliot Daly, Owen Farrell and Greig Laidlaw are all proficient goal kickers but will be under consideration for positions other than fly-half.
It is difficult to see Jonathan Sexton being left at home but one - or maybe two - of Dan Biggar, George Ford and Finn Russell will likely be omitted, given the depth of kicking talent.
Hogg was one of the standout performers of the Six Nations, scooping the player of the championship award, and is tipped by many to be handed the Lions' Test 15 jersey.
With Liam Williams and Halfpenny able to play across the back three, it could spell trouble for full-back specialist Mike Brown's chances, while the versatility of England team-mate Daly may also keep him out.
Rob Kearney's inclusion will be dependent on him being able to shake off arm and knee injuries.
Gatland is not short of options on the wings, with George North, Anthony Watson, Simon Zebo and Tommy Seymour also pushing for a place.
One intriguing aspect of Gatland's squad will be whether he opts for anyone currently outside the national set-ups of England, Ireland, Scotland and Wales.
New Zealand-born code hopper Denny Solomona has impressed since leaving Castleford Tigers for Sale Sharks and has declared himself available for England selection.
Chris Ashton's England career may be over as he prepares to head to Toulon next season, but he could be in Gatland's thoughts, as might Clermont Auvergne's Nick Abendanon.
Veteran Welsh hooker and 2013 tourist Richard Hibbard has also been mentioned after some fine performances for Gloucester, but Danny Cipriani's chances of sneaking in look slim due to the aforementioned options in his positions.