* Blatter calls for unity as Congress opens
* Unlikely to be unseated by sole challenger
* Award of World Cups to Russia and Qatar a problem
ZURICH - World soccer boss Sepp Blatter was expected to be re-elected on Friday, defying growing calls for him to step down in the face of corruption scandals engulfing the sport's governing body.
Addressing FIFA delegates at the body's annual Congress in Switzerland, where members will later vote to decide the organization's presidency, Blatter promised more transparency and urged members to remain unified.
He also said that FIFA would probably not be facing its present problems if Russia and Qatar had not been awarded the 2018 and 2022 World Cups, respectively.
"Today, I am appealing to unity and team spirit so we can move forward together," he said, in a low key-address that contrasted with his more defiant reaction on Thursday.
Blatter also sought to distance himself from the scandal, the biggest crisis FIFA has faced in its 111-year history.
U.S. authorities have accused top FIFA figures and sports executives of corruption, while Switzerland is separately investigating the award of the next World Cup finals to Russia and Qatar.
"We cannot watch everyone all the time. We have 1.6 billion people directly or indirectly touched by our game," Blatter said.
He recalled that the Russian and Qatar awards were announced together in 2010 and "if two other countries had emerged from the envelope I don't think we would have these problems today."
His opening address was briefly interrupted by a female protester waving a Palestinian flag and shouting at Blatter before being removed. The Palestinians are seeking to have Israel suspended from FIFA at the Congress.
Blatter, who has been heavily criticized for not doing enough to combat corruption in FIFA, is being challenged by Jordanian Prince Ali bin Al Hussein for the most powerful job in soccer.
Anger within Europe's powerful regional soccer body UEFA and other members over the damage allegations of bribery and corruption are doing to FIFA is unlikely to be enough to topple the 79-year-old Swiss, who is backed by the Asian and African confederations and many Latin American states.
English Football Association chairman Greg Dyke said England would support a possible boycott of the 2018 World Cup if Blatter was re-elected president of FIFA.
But the numbers appear to be in Blatter's favor, despite some countries saying they were switching allegiance and predicting that the scandal would finish Blatter as FIFA chief.
Most of the developing world in Africa, Asia and parts of Central America and the Caribbean are reluctant to vote for change in FIFA leadership given that the organization guarantees them annual grants and bonus payments in World Cup years.
Kuwait's Sheik Ahmad Al-Fahad Al-Sabah, one of the most powerful men in world sport, said Blatter is the right man for the job and should be re-elected.
"FIFA should have a leader with a lot of experience," the FIFA executive committee member told Reuters at Zurich's Baur au Lac hotel, where seven FIFA executives were arrested on Wednesday.
On Friday, New Zealand Football said it would vote for 39-year-old Prince Ali despite a previous unanimous commitment from countries in the Oceania Football Confederation in January to back Blatter. Canada also said it would not support Blatter.
Nine soccer officials and five sports media and promotions executives have been charged by U.S. prosecutors with corruption the authorities said involved more than $150 million in bribes.
Swiss authorities also announced a criminal investigation into the awarding of the next two World Cup tournaments, which are being hosted in Russia in 2018 and Qatar in 2022.
Both countries deny any suggestion of wrongdoing over their bids to host one of the world's top sporting events, and Russian President Vladimir Putin has accused the United States of meddling in an effort to prevent the re-election of Blatter.
Adding to the pressure on FIFA and Blatter, there are growing concerns from major sponsors, many of whom have solidly backed the organization despite nearly 20 years of bribery and corruption allegations.
German sportswear company Adidas said FIFA should do more to establish transparent compliance standards. Anheuser-Busch InBev, whose Budweiser brand is a sponsor of the 2018 World Cup, said it was closely monitoring developments.
Credit card company Visa Inc urged immediate reforms.
"It is important that FIFA makes changes now so that the focus remain on these going forward. Should FIFA fail to do so, we have informed them that we will reassess our sponsorship," it said in a strongly worded statement.
Coca-Cola Co, another sponsor, said the charges had "tarnished the mission and ideals of the FIFA World Cup and we have repeatedly expressed our concerns about these serious allegations."
The corruption scandal is unlikely to go away soon, as investigations into wrongdoing widen.
A judge in Argentina ordered the arrest of three businessmen accused of conspiring to obtain lucrative media rights contracts from regional soccer federations through the payment of up to $110 million in bribes.
In Brazil, the Senate, led by former national soccer star Romario, now a legislator, moved to open a formal inquiry into bribes that authorities said were paid to obtain contracts with the Brazilian Soccer Federation.
The Miami-based Confederation of North, Central American and Caribbean Association Football (CONCACAF) president Jeffrey Webb, who was among those arrested, has been provisionally dismissed from his role, the confederation said on Thursday. (Writing by Mike Collett-White and Giles Elgood; Editing by Peter Graff)