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
[UPDATE 10/10 @ 12:26am]
The media learned on October 8 that Kubo is expected to have surgery to treat the blood flow condition in his fourth and fifth fingers. Kubo apprently decided to go under the knife because his recovery was taking longer than expected.
Source: Sports Hochi 10/9/2017