So who will replace Liverpool Walton's Peter Kilfoyle?
Liverpool's former Lord Mayor Steve Rotheram is likely to emerge as the local frontrunner to replace Walton MP Peter Kilfoyle.
Cllr Rotheram represents the Fazakerley ward which sits inside the ultra-safe Labour seat, where the party has a majority of almost 16,000.
Had there been an open selection for Liverpool Wavertree he would have been a favourite for that seat.
He can lay claim to an even closer tie with this seat.
Deputy Liverpool Labour leader Paul Brant would also be expected to be in with a strong shout for the seat.
And Gary Booth, who works in Mr Kilfoyle's office, may also fancy his chances.
But it will all depend on what the Labour party's National Executive Committee decides to do.
The NEC will once again decide whether to have an open list or an all women shortlist. And then it will give the local party a shortlist to choose from, so we can expect some national Labour party figures to emerge.
In his resignation letter Mr Kilfoyle writes: 'That choice is, of course, entirely yours; but I hope that your choice will reflect the needs of Walton and Liverpool for local representation - someone with a feel for, and knowledge of, both Liverpool and the Labour Party.'
Many wondered what he was playing at when he attacked Luciana Berger for not being local and a student politician when she was chosen for Wavertree.
It now looks like he was setting down a marker.
As he said in his resignation letter: "Much of political life is an illusion, to both the participant and the observer."