Japanese long-distance runner Yoko Shibui made a dream marathon debut Sunday, winning the Osaka International Women's Marathon with the fastest time ever for a first-timer.

Shibui ran alone for nearly half of the 42.195-km course before crossing the line at Nagai Stadium in 2 hours, 23 minutes, 11 seconds. Franca Fiacconi of Italy finished a distant second in 2:26:49 with Japan's Rie Matsuoka third in 2:27:50.

Featuring a typically weak field in a post-Olympic event, the race soon developed into a three-way battle between Shibui, Restituta Joseph of Tanzania and Ethiopian Elfenesh Alemu after the first 5 km.

But Joseph and Alemu, sixth at the Sydney Olympics last September, faded out of contention around the halfway point, allowing Shibui to make a solitary journey the rest of the way, flirting with the Japanese record of Olympic hero Naoko Takahashi.

The 21-year-old Shibui's time is the fourth best on the all-time list of Japanese female marathoners and the 12th fastest women's run ever.