Golden Bat by Sandy Fussell

Samurai Kids Book 6. Walker, 2011. ISBN: 978 1 921529474.
(Age 10+) This is the sixth book in the series. A group of young Japanese teens are being trained as Samurai by an ex-warrior, Sensei, also known as Ki-Yaga. Each of the teens not only have a talent to contribute to the team (despite handicaps) but also have a spirit to guide them. Taji's spirit is the golden bat. Taji is blind but his hearing has become acute. After their team mate, Mikko, is taken hostage by the feared pirate Captain Oong, a deal is struck between the pirate and Sensei - rescue the pirate's nephew, Yuri, from a corrupt Chinese magistrate and their friend and student will be returned.  But they only have eight days to complete their task.  If they fail Mikko will be harmed.  As the group travel across the countryside, they have adventures along the way. Time starts to run out. Will they be able to deliver Yuri in time? What will happen if they don't?
Janet Cassidy