Jim McIntyre has warned his basement boys they have got three games to prove they can play a part in Dundee's fight for survival.
The Dens Park boss is planning a major overhaul of the struggling squad he inherited from Neil McCann when the transfer window opens the week after next.
The Dark Blues are back at the bottom of the table following Tuesday's crushing 5-1 defeat by Aberdeen and McIntyre admits he desperately needs new recruits.
That Dons drubbing has wiped out the feel-good factor generated by the mini-revival which saw them pick up four points from six against Hamilton and Rangers, but McIntyre is willing to give the players who let him down at Pittodrie another chance.
However, he says those who fail to show up against Celtic this weekend and the subsequent clashes with Livingston and St Johnstone before the winter break risk being replaced.
McIntyre said: "I know exactly what needs to be done but doing it is another thing. You need the right types – the right type of mentality and the right players available at the right time.
"So we'll see how we get on with that.
"Yes of course there are players who have got an opportunity over the next three games to send a message out.
"But I need to see better than what I saw the other night."
Dundee have shipped eight goals in their last two games against Kilmarnock and Aberdeen.
But he is still willing to give his side a chance at toppling Brendan Rodgers' league leaders.
"I've been to Celtic Park several times with my Ross County team and picked up points, so it can be done," he said.
"You've got to go into every game believing you can get a result.
"We know that we need to have one to 11 right bang at it and we need a few of Celtic's players dip below their normal levels.
"It's 11 v 11 and you never know.
"You need to be structured, organised and difficult to break through as Celtic have such an array of talent that they can hurt you in the blink of an eye.
"We need to make sure our concentration levels are spot on."
