All will be revealed just after noon tomorrow when Warren Gatland names his Lions skipper at 12.15 followed by his 36-man squad at 12.30 for the tour to South Africa.
In mid-April, Gatland gathered his coaching team - including Leinster's Welsh forwards coach Robin McBryde and Scotland head coach Gregor Townsend - for an initial selection meeting and the names of 57 players were thrown into the pot, with the group agreeing on about half of that number.
Gatland has been here before, having brought the Lions to Australia and New Zealand, and has been putting together combinations based on form, fitness and suitability for an intensive tour schedule.
Where Johnny Sexton fits into his thinking is the headline news for Ireland rugby fans.
So integral to the success of the last two Lions tours, Sexton celebrates his 36th birthday in July and he hasn't played since coming off against Exeter Chiefs having suffered his third head injury since February.
Gatland has a lot of faith in Sexton's abilities, but does the former Wales supremo have faith in his ability to endure the physical demands of what's to come?
If Ireland's captain doesn't go, it will be a shock.
By our reckoning, there are six Ireland players definitely on the plane, though more will surely go. But there could be a few sleepless nights tonight.
DEFINITELYS
Tadhg Furlong
Has been outstanding since his return after a year-long absence. World-class tighthead who the beefy Springboks front row will fear.
Robbie Henshaw
Came into his own this spring and in the Six Nations. Likely Lions Test starter after unleashing his running and passing game.
Tadhg Beirne
Came to life for Ireland in this year's championship with his impressive all-court game and will provide vital cover in the back row and second row.
Conor Murray
Has gone from a place where his ticket to South Africa was in real jeopardy to being in the running to start against Springboks.
Iain Henderson
Would be a big surprise if he didn't make it. Will travel because he can cover second row and back row and has been excellent since returning from injury.
James Ryan
A banker at Christmas, Ryan's hopes of battling for a Test start against Alun Wyn-Jones and Maro Itoje have faded due to injury and a struggle to regain form, but should make it.
MAYBES
Johnny Sexton
Was the top no 10 at the Six Nations and has started the last five of six Lions Tests. A better, more consistent performer than Dan Biggar and Finn Russell - but questions remain over his durability after recent series of head injuries.
Garry Ringrose
Similarly to James Ryan, was pushing for a Lions start before an injury-hit run. Yet to regain his rhythm.
Andrew Porter
Did very well for Leinster and Ireland before Tadhg Furlong's return and that should be enough to get him on the plane.
LEFT FIELD
Hugo Keenan
Ireland's most consistent performer since lockdown ended, having played every minute of every Test since. But Gatland has huge back three options in terms of experience and dynamism.
Rónan Kelleher
Storming performances against England and Exeter suggest he could be a Lions bolter, but Rob Herring was more trusted by Irish management during Six Nations.
Rob Herring
Solid performer for Ulster and Ireland whose throwing and ruck work will have earned him consideration, but England duo and Ken Owens expected to travel.
Jacob Stockdale
Endured a difficult time of it post lockdown in Paris and then through injury, but back on song now. Again, the back three is flooded with strong candidates and expected to lose out.
ON STANDBY?
CJ Stander
Soon to retire, the Munster back row's versatility could get him the nod this afternoon but if he's back home in South Africa then would be a great option to have in reserve.
John Cooney
Interestingly has entered the debate late in the game after some big displays of late for Ulster, including against Leicester. One who will be on stand-by.
Keith Earls
The veteran speedster finished the Six Nations in flying form. It would be some story if at some stage he got the nod to join the squad, 12 years on from his one and only tour in South Africa.
Josh van der Flier
Had a real purple patch with his displays against England and Exeter, but like many Leinster players didn't drive that home against La Rochelle last weekend.
Peter O'Mahony
Skippered the Lions in the first Test in New Zealand and Gatland likes him, but the Munster captain has already ruled himself out of contention after the red card in Cardiff saw him miss three Six Nations games.
