Yuki Saito was scheduled to pitch a couple of innings during a Ni-gun game against Rakuten at Kamagaya earlier today. He took the mound in the sixth inning and promptly surrendered a home run to Takumaru Yaoita. He then took a line drive off his right shin/ankle. He temporarily left the field for treatment and returned to finish the inning (1.0 IP, 3 H, 2 R), but was replaced in the seventh as a precaution. He told reporters after the game that he was fine.
[UPDATE 5/12 @ 6:04pm]
Saito did not require a visit to the hospital. There is some swelling and a little internal bleeding on the outer side of his right shin.
Source: Nikkan Sports 5/12/2017