Yuya Kubo was taken off the active roster today because he might have a blood circulation problem in his right fingers. He is expected to get tested at a hospital shortly.
Kubo complained of numbness in his right fingers after his last outing on September 7 against Nippon Ham at Tokyo Dome.
Source: Sports Hochi 9/9/2017
[UPDATE 9/14 @ 8:03am]
Kubo was examined at a hospital and diagnosed with decreased blood flow in the fourth and fifth fingers of his right hand. Since the condition is temporary, there will be no need for surgery.
Source: Nikkan Sports 9/13/2017