Put up or push off. Labour isn't saying it out loud but if David Shearer doesn't deliver on Sunday he won't lead the party into the next election.
Shearer has to shut down the corrosive speculation about his leadership, show the annual conference in Auckland he has the grit and the determination to win, and look like a prime minister in waiting.
If he doesn't the whispering will go on, the bloggers and the mainstream media will continue to focus on his failings, and he won't survive it.
Right now he isn't under threat. There isn't a challenger, no one is running the numbers and his MPs are making heroic efforts to persuade the media and the public their support is rock solid.
It won't last unless Shearer convinces his caucus, and about 600 delegates, that they made the right choice in December last year.
The former UN aid worker is caring, compassionate and a genuinely nice guy - even the prime minister says so.
But it was something else John Key said that cuts to the core of Labour's uncertainty: "I've seen tougher leaders. Helen Clark was much, much tougher. Even Phil Goff was."
Shearer is too laid back, doesn't go for the government's throat, doesn't land punches in parliament and isn't confident in front of the media.
Without a script he often loses his way, mixes up his words and lacks impact. What that adds up to is looking as though he doesn't know what he is talking about, or if he does he isn't sure he means it.
Shearer says he is working on that. Goff, who stood down after losing the last election, suggests it's just a matter of experience.
"Yeah, he's got things to learn, he's new to the job but he's got the integrity, he's got the ability, he's got the determination to do the job."
David Cunliffe, beaten by Shearer in the leadership contest, is more articulate, stronger in parliament, and seriously nasty when he takes on government ministers.
He is a former cabinet minister, while Shearer came from the back benches.
Cunliffe's caucus colleagues don't like his ego but unless Shearer can show he has got what it takes they're going to start thinking they could live with that.
In the run up to the conference, the first he will address as party leader, Shearer has been trying to counter his critics.
Labour, he points out, is more popular now than it was when it lost the 2011 election.
It is, but it came off a low base - its worst-ever defeat with 27.5 per cent of the vote. Now it hovers around 33 per cent and the government, after the horrendous first year of its second term, leads Labour by more than 10 points.
Labour needs Shearer to succeed on Sunday.
It needs a leader who unequivocally says what he believes in, takes ownership of policy and takes the fight to the government's front bench.
Shearer has been in the job for 11 months and the questions are still being asked: What does he really stand for, what is he really like?
Maybe he will tell his party on Sunday. He needs to.