Six reasons why Sepp Blatter chose to resign now as president of Fifa

On hearing Sepp Blatter's reasons for resigning yesterday, FA chairman Greg Dyke told BBC Radio 5 Live: "I don't believe a word of this. If he believes that why not step down last week when we asked him to?"

Indeed, Blatter's explanation that his mandate as president of Fifa is not supported by "the entire world of football" can hardly have come as a surprise to the 79-year-old Swiss.

Following last Friday's presidential election in which he won the support of 133 of Fifa's 209 associations, Blatter was, as Dyke explained, "cock-a-hoop" and "terribly arrogant".

So why resign now?

1. Intense media scrutiny

Following on from the stellar investigative work of the likes of journalists Andrew Jennings, Heidi Blake and Jonathan Calvert, Blatter has come under intense media scrutiny in the past few weeks. In a series of pained press conferences, Blatter has been forced to bat away repeated questions over his position and integrity following the arrests of several senior Fifa officials last week.

Meanwhile, Interpol has released a list of "most wanted" Fifa officials, or as the Media Blog put it:

2. Pressure from sponsors

Following accusations of "rampant, systemic and deep-rooted" corruption last week, Visa threatened to pull its support if Fifa did not reform and implement "strong ethical practices".

With major sponsors like Coca-cola and Adidas - among those who have helped Fifa become the multi-billion dollar organisation it is today - also expressing concern, perhaps the threat of lost revenue pushed Blatter out of the exit door.

3. Uefa boycott

Member associations from football's traditional heartland have been the most outspoken in their desire to oust Blatter. Uefa organised a meeting in Berlin on Friday to discuss the possibility of a breakaway World Cup in 2018. As Sam Wallace explains, a Fifa World Cup without the giants of European football, as well as selected South American countries would be "fatally undermined in the eyes of the fans and sponsors".

4. The Valcke letter

On Tuesday morning a letter was revealed detailing a $10m payment that is alleged to have been a bribe paid by the South African FA to Jack Warner - the former head of Concacaf.

The fact that the letter included the name of Sepp Blatter's second-in-command Jerome Valcke, in Ian Herbert's words, "put this scandal closer than is comfortable to the man from whom this culture has flowed".

5. A job offer from the Kremlin?

A long term ally and one who took a close personal interest in Russia's bid for the 208 World Cup, Vladimir Putin was highly supportive of Blatter in spite of last week's scandal.

Putin branded the FBI investigation into Fifa was an "illegal exterritorial use of US law" and was only being done in "order to achieve their own selfish gains".

The Independentreports that many now believe Blatter's next job after leaving Fifa could be as an ambassador for... Russia's 2018 World Cup.

6. A smoking gun?

Andrew Jennings, the journalist who helped the FBI with their investigation into Fifa corruption, let out an ominous warning after the arrests last week:

Following Blatter's resignation on Tuesday, reports in the US suggested that Blatter was now subject to investigation by lawmakers.

As Greg Dyke said in that same impassioned interview: "Clearly there is a smoking gun of some sort. This is nothing to do with Mr Blatter being honourable. He hasn't been honourable for years."

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