Swiss Blatter is bidding for a fourth term as president in next month's vote with Asian football chief Bin Hamman standing in his way. As the days tick down to June 1 both are becoming increasingly outspoken.
In an open letter sent to European media, Blatter pulled no punches on Friday.
"What is actually at stake?" said the 75-year-old who has been dealing with fresh allegations this week about four FIFA Executive Committee members asking for favours in return for votes in last year's decision on hosting the 2018 and 2022 World Cups.
"The FIFA presidential election is not about candidate A or candidate B, it is about whether there will be any candidates at all in future. The ballot on June 1 could lead to a seismic shift with irreversible damage.
"Quite simply, the survival of FIFA is at stake. It is a question of whether the game's established world governing body will continue to exist after this date or whether it will disappear into a black hole."
Blatter is favourite to survive the challenge of Bin Hamman and has the support of European governing body UEFA's executive committee, a potentially decisive factor in the outcome of the vote for one of the most powerful position's in world sport.
"Is it that dramatic?" you may ask," Blatter went on. "The answer is, theoretically, yes, it is.
"I am confident that I will win the election with a clear two-thirds majority. South America, Central and North America, Europe, Oceania and a significant part of Africa and Asia will continue to support my ideas. Nevertheless, it is worthwhile outlining what the alternative would be, i.e. none at all."
Blatter went on to use a typically colourful analogy to describe the consequences of defeat.
"What applies for every carpenter also applies for us: the roof will only hold as long as the foundations are in place," he said. "If the ground beneath crumbles, the entire edifice will collapse. And that is precisely what is at stake on June 1. All or nothing!"
Blatter's outburst comes the day after Bin Hammam criticised his rival for making a $20 million donation to Interpol to help combat match-fixing - accusing him of acting alone and without consulting FIFA's executive committee.
"It is just another example of the current regime choosing to run football how it sees fit, rather than doing so in a manner that is consistent with the governing body's proper procedures," Bin Hammam said.
