Wind Mill

Wind Mill (ウインドミル) is a manga series by Takashi Hashiguchi. It was serialized in Shounen Sunday.

Plot
Hirosawa Taki has practically grown up with a bowling ball in her hand. Her physical shape is great, and she can look forward to an amazing career in that sport - until one day, a series of chance occurrences brings her into contact with a sport she's never considered before: softball. She tries it, and finds she likes it. Not only that, but she's monstrously good at it.