UPDATE 1-Microsoft Xbox 360 outsells PS3 in Japan in Sept

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TOKYO, Oct 3 (Reuters) - Microsoft Corp's (MSFT.O) Xbox 360 outsold Sony's (6758.T) PlayStation 3 in Japan in September, beating the rival machine in monthly unit sales for the first time in Sony's home market, a game magazine publisher said.

Strong sales growth came after Microsoft cut prices for its game console last month.

Microsoft sold 53,547 units of the Xbox 360 in the four weeks to Sept. 28, compared with 33,071 units of the PS3, data from Enterbrain showed on Friday.

Nintendo Co Ltd (7974.OS) safely maintained its leading position in the Japanese console market, having sold 109,548 units of the Wii during the month.

Although popular in the United States, the Xbox 360 has been struggling to compete with the PS3 and the Wii in Japan, home to both Sony and Nintendo.

In a bid to lift sales, Microsoft on Sept. 11 cut the price of the Xbox 360 Arcade, which comes without a hard disk drive, by 8,000 yen ($76) to 19,800 yen. It also lowered the price of the high-end Elite model by 8,000 yen to 39,800 yen.

Sony sells the PS3 with a 40-gigabyte hard disk drive for 39,980 yen, while Nintendo offers the Wii for 25,000 yen.

The Microsoft console also got a boost from Square Enix Holdings' (9684.T) popular role-playing game, "Infinite Undiscovery", launched in Japan on Sept. 11.