The Finance Secretary, Mark Drakeford, is to announce that he will stand in the contest to become the next Welsh Labour leader and First Minister.
It makes the Cardiff West AM the first to declare his intention to try to take over from Carwyn Jones who's said he'll step down as leader in the autumn and as First Minister at the beginning of December.
In order to take part in the contest, prospective candidates need to be nominated by six Labour AMs (including themselves). Mark Drakeford has the support of eight colleagues. They are:
The move shows how well organised and advanced the campaign behind Mark Drakeford is. He's seen as the candidate most favoured by the left of the party which has grown in influence in recent years.
There's been speculation too that he's reached an agreement with fellow cabinet member and someone who had also been spoken of as a likely contender, the Economy Secretary Ken Skates which would see Mr Skates act effectively as Deputy First Minister, keeping his current portfolio.
That suggestions has been criticised by some I've spoken to as 'a sneaky deal' but a member of the campaign team says 'I can absolutely assure you there has been no 'deal' about a Deputy role.'
While he's clearly well ahead of other candidates, Mark Drakeford is still likely to face a challenge.
There's a feeling amongst Labour members that the choice to replace Carwyn Jones shouldn't result in a coronation, but that it should be a contest. .
Speaking on Sharp End, the Labour AM for Merthyr, Dawn Bowden said there should be a contest.
It could be a coronation and I hope it's not. I hope it is a contest. That's good for our democracy within the party and within the Assembly.
It's almost certain that Health Secretary Vaughan Gething will stand although he's not yet commented.
There are many within Labour who say it's unthinkable that the contest would take place without a woman candidate on the ballot paper.
That candidate seems certain to be Eluned Morgan who I understand is being urged by a number of women to stand and has won the support of some AMs.
On Sharp End I asked Dawn Bowden if there needs to be a woman as a candidate. She said:
I'm certainly of the view that there should be a woman. In 2018 for Welsh Labour to be running a ballot without a woman would be unthinkable.
There are also those who think there needs to be not just a contest but a full contest with the maximum four candidates which the rules and Labour Assembly group maths allows, at least in the early stages.
From what I gather if there were to be a fourth candidate, that could be Huw Irranca Davies who has UK Government ministerial experience but will be considered the underdog in this election.
There's still the question of Alun Davies who's said he would only consider standing if the election is held using one member one vote.
As things stand, that won't be the case because the next leader is due to be chosen using the electoral college system.
That's been at the centre of controversy within the party, a controversy which has intensified after the weekend's announcement of Welsh Labour's first Deputy leader.
The contest was won by Swansea East MP Carolyn Harris who won the support of affiliates and parliamentarians in the electoral college while Cardiff North AM Julie Morgan won the support of members.
At Welsh Labour's conference in Llandudno at the weekend, Carwyn Jones announced a democracy review into the way the party's internal elections are held to report by the time of the next conference in 2019.
However there have been calls for change to come earlier so that party members have a bigger, if not the final say, in the choice of leader.
Julie Morgan has joined those calls and has launched a petition backed by fellow AMs Jane Hutt and Julie James.
The Cardiff North AM said:
Of course I accept the result as I stood knowing the electoral college rules however it really does seem wrong to me that that a small number of parliamentarians and trade union activists were able to have a greater say than members.
In another development, it's become clear that Carwyn Jones' final months as First Minister will be dominated by the QC-led inquiry into his sacking of the late Carl Sargeant and handling of the allegations made against him.
Paul Bowen the QC appointed with the agreement of the Sargeant family has written to potential witnesses saying that he's planning to take evidence in hearings during the weeks beginning 18th and 25th June and between 3rd and 28th of September.
That's later than many had hoped for and makes it unlikely that the QC's report will be published before Carwyn Jones leaves office.