Sony’s PlayStation 3 video-game console topped Microsoft’s Xbox 360 in U.S. unit sales for the first time in January, but the Redmond company said its sales were hurt by supply shortages.

The PlayStation 3 sold 269,000 units for the month, according to statistics released by the NPD Group market research firm. That was just behind Nintendo’s Wii, which sold 274,000 units, NPD said. Microsoft sold 230,000 Xbox 360 consoles.

“We certainly believe that this is an anomaly,” said Microsoft spokesman David Dennis of the Xbox 360’s third-place finish.

The company said this week that higher-than-expected demand for Xbox 360 during the holidays caused subsequent shortages.

Sony, in a statement, pointed to progress in areas including movie studios’ embrace of the Blu-ray next-generation DVD format, which the PS3 uses. Jack Tretton, Sony Computer Entertainment America chief executive, said that it’s “shaping up to be a breakthrough year for us.”

Sony’s PlayStation 2 dominated the previous console generation, but the PS3 has struggled to find its footing.

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