Special report from the BBC's Pete Oliver.
 |  (If Wrexham go down) the local derby would be against Northwich Victoria and you wouldn't get 1,000 people in Brian Flynn |
Macclesfield are also involved in their version of relegation Russian roulette and could bite the bullet if they lose their crunch game at home to Notts County.
But Wrexham and Boston both know that they can save their own skins and in most probability send the vanquished down into the Conference when they clash at the Racecourse Ground.
For troubled Boston, whose financial and injury woes mean they can hardly raise a team, nothing but three points will do if they are to avoid a return to non-league after four seasons in League Two.
For Wrexham - three times FA Cup quarter-finalists and a Championship club 25 years ago - such a fall from grace would be almost unthinkable should they not secure at least the draw they need.
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"It would be a disaster," said Wrexham legend Brian Flynn, who managed the club between 1989-2001.
"I had 14 years there as a player and a manager and for me that would be down the drain if it happens.
"The local derby would be against Northwich Victoria and you wouldn't get 1,000 people in."
Flynn would also have wider worries for the impact on football in Wales should the country lose another League club following the fall of Newport County in 1988.
 Jones is one of the players off the Wrexham production line |
"Wrexham has been a major production line of young players," said the former Wales international, who is now coach of his country's under-21 side.
"Our under-17s recently went to Turkey and we had five Wrexham boys in the squad.
"I am not saying they will make senior internationals but four could play first-team football and if four are coming through to challenge for a first-team place who knows?"
However, Flynn believes that the omens are positive in Wrexham's quest to survive.
The Dragons go into the game with some solid form behind them. A run of three successive wins - their best of the season - was only ended last weekend with a tight 1-0 defeat at League Two leaders Walsall.
That contrasts with a position at the end of February when Wrexham were second from bottom of the table and without a win in 12 games - a sequence which had seen the managerial reins pass from Denis Smith to former defensive stalwart Brian Carey.
"I was talking to Brian a few weeks ago and I said that if he had a win against Boston at home on the last day to stay up he should take it now," said Flynn.
"At least they have got a lifeline and you have to have a lifeline.
"It looked ominous a few months ago. The vital signs did not look good but I have seen them twice in the last couple of weeks and the signs are back.
| Wrexham's management have got good plans, but they have to be in the Football League Brian Flynn |
"The signs you need to be showing are there. They won three times and kept three clean sheets, which they had not been doing."
Flynn added: "With 20 games to go and you're in the bottom two players don't understand the situation.
"When it really hits home is when there are five games left and you're still in relegation trouble.
"That's when it really kicks in and you've got to get them focussed, fit and mentally strong.
"Out of the last four they have won three and lost one to a side which is already promoted, so the signs are there."
Saturday's game mimics final-day deciders between Hereford and Brighton in 1997 and Torquay and Barnet in 2001.
On those occasions the away team got the result they needed as Brighton and Torquay avoided the drop.
Flynn does not want Wrexham to allow the hat-trick and will be among an anticipated 10,000 draw at the Racecourse, scene of the famous 1992 FA Cup slaying of Arsenal, to help spur them on to the result they require.
He said: "Players move on. That has always been the case. But all the staff are still there. They were my work colleagues but they were also my friends.
"They are still friends and I will be there to hopefully see them survive."
 Flynn says Dickens and Geoff Moss have big plans for Wrexham |
Having come through off-the-field battles, including a period in administration which contributed to their relegation from League One two years ago and threatened their survival, Wrexham are trying to rebuild under the new ownership of Neville Dickens and Geoff Moss.
"They have got good plans. The two people there are forward-thinking, hard-nosed business people who will get things done.
"The club will be run properly, but it has to be in the Football League," said Flynn.
And if Wrexham do stay up, Flynn believes in Carey they have a promising young manager.
Flynn signed the 38-year-old, another budding boss educated at Old Trafford by Alex Ferguson, both on loan and on a permanent basis during his Wrexham days and believes Carey is made of the right stuff.
"He has got a very good chance of being a good manager if he comes through this. He is leadership material," added Flynn.
"This is a major test for him but having been with him and talked with him his demeanour is excellent and he knows what he wants."