Keizo Kawashima took a hard slide from Kensuke Tanaka while playing second base in the sixth inning against Nippon Ham on April 3. He was replaced on defense after the play and taken to a hospital. He was diagnosed with a bruise on his lower right leg. The Softbank Hawks are planning to file a complain with the Pacific League for a slide they feel umpires should have questioned.
[UPDATE 4/4 @ 10:08pm]
Kawashima was taken off the active roster on April 4. The bruise on his right leg was apparently pretty bad because he needed crutches to get around on April 3.
[UPDATE 4/5 @ 9:43pm]
The media learned today that Kawashima not only suffered a bruise on his leg, but also damage to the anterior talofibular ligament and calcaneofibular ligament. He will need to keep his right ankle immobile for about three weeks. There is no timetable on how long it will take for a full recovery.
Source: Chunichi Sports 4/5/2016