Former world chess champion Bobby Fischer has applied for political asylum in Japan.
The US says Bobby Fischer's passport is no longer valid
He has also appealed against a decision to deport him to the US, where he has been wanted for more than a decade.
Mr Fischer faces a possible fine or even a jail term if he is sent back to the US.
The controversial genius is accused of breaking international sanctions by visiting Yugoslavia in 1992 to play his former arch-rival Boris Spassky.
The reclusive Mr Fischer, an American citizen but a fierce critic of US government policies, was detained at Tokyo's Narita airport on 13 July, travelling on what the US claims was an invalid passport.
He had managed to live undetected in Japan for three years, sometimes travelling abroad.
This time he was reportedly on his way to the Philippines.
Nov 2003 - US embassy in Switzerland extends Fischer passport
15 April 2004 - Fischer enters Japan
June - US tells Japan passport revoked
13 July - Fischer taken into custody trying to fly to Philippines
Mr Fischer filed a plea against deportation last week, which was rejected by Japanese immigration officials. As expected, he filed a second plea on Monday.
A Justice Ministry official said no decision was likely to be made on this appeal for a few days.
Mr Fischer has also opened up another avenue for appeal, by seeking asylum in Japan.
According to our correspondent in Tokyo, Jonathan Head, this is a desperate measure in a country which accepted only 18 refugees last year.
But the two-pronged approach could well give Mr Fischer valuable time to investigate all the alternatives open to him.
His supporters are said to be trying to obtain travel documents from a third country - possibly Germany, where his father was born - so that he could be flown there instead of the US.
Now holed up in a detention cell at Tokyo's international airport, the circumstances of the one-time world champion have never looked bleaker, our correspondent says.
A brilliant but highly mercurial player, Bobby Fischer became a grandmaster at 15 and shot to fame in 1972 when he beat Boris Spassky of the then-Soviet Union.
The match, played in Iceland, was billed as the "Match of the Century", and Mr Fischer's win was regarded as a propaganda victory as the game had been dominated by the Soviets since World War II.
He held the title of world chess champion until 1975, and then slipped in and out of the limelight, resurfacing in Yugoslavia for the dramatic 1992 rematch against Mr Spassky.
He won the match, but disappeared when the US authorities announced they wanted to prosecute him over the $3m he earned for playing, which the US said violated US and UN bans on doing business there.
Mr Fischer has since reappeared sporadically, making strong attacks on what he called "world Jewry", and calling the 2001 terrorist attacks on the US "wonderful news".