Baby Steps

From K-Manga:
Eiichiro Maruo is a straight-A student who decides to take up tennis as a side hobby upon entering high school. At the tennis school, he runs into Natsu. A bit airheaded, but nobody can beat her in passion for the sport. Soon, Eiichiro gets addicted to tennis and when he applies his academic skills to improving his game, the results will change his life forever!

Note: Won the 38th Kodansha Manga Award in the Best Shōnen Manga category in 2014.