Shun Yamaguchi started spring camp at San-gun because of discomfort in his right shoulder. No issues were discovered in the shoulder during an examination on February 2. He was hoping to join the Ichi-gun team during Okinawa camp, but the Yomiuri Giants are not going to rush him with a set schedule. The Giants believe he will be fine for opening day if he can pitch in one or two exhibition games.
Yamaguchi has played catch three days in a row. He is also up to fifteen meters on throws into a net. He could be ready to toss a bulpen session before the end of the month.
Source: Nikkan Sports 2/4/2017
[UPDATE 3/4 @ 2:26am]
Yamaguchi may not be ready to join the Ichi-gun team until mid-April. His condition is improving, but the last thing the Giants want is for him to re-aggravate the shoulder.
Source: Sanspo 3/3/2017
[UPDATE 4/28 @ 7:43pm]
Yamaguchi tossed batting practice at Giants Stadium earlier today. He faced Ikusei players Kosei Tajima, Shuhei Kato, and Takuya Kawai. He threw fifty-eight pitches, allowed five could-be hits, and topped out at 139km/h. He threw sliders and fastballs at sixty to seventy percent.
Source: Nikkan Sports 4/28/2017
[UPDATE 4/30 @ 7:08pm]
Yamaguchi might be ready to play in his first rehab game some time around May 10. The Giants will probably have him pitch in two to three rehab games before they consider moving him up to Ichi-gun. That could mean some time around the end of Inter-league play.
Source: Nikkan Sports 4/30/2017
[UPDATE 5/5 @ 5:25pm]
Yamaguchi tossed another batting practice again today. He threw sixty-one pitches (all fastballs) and faced Takehiro Donoue and Kazuma Okamoto. He threw thirty-one pitches to Donoue and allowed five could-be hits, including a home run. He threw thirty pitches to Okamoto and allowed eight could-be hits, including three home runs.
Source: Nikkan Sports 5/5/2017
[UPDATE 5/11 @ 5:58pm]
Yamaguchi tossed a bullpen session on May 9 and threw into a net on May 10. He pitched in a batting practice scrimmage today and faced ten hitters. He threw thirty-four pitches at about eighty percent, allowed two could-be hits, and topped out at 144km/h.
[UPDATE 5/12 @ 6:10pm]
Yamaguchi might be ready to pitch in a Ni-gun rehab game on either May 17 or 18. If he continues to make good progress, he might be able to make the active roster in early-June.
[UPDATE 5/17 @ 9:52pm]
Yamaguchi is slated to pitch two innings in a Ni-gun game against Yakult at Giants Stadium on May 18. He threw forty-eight pitches in the bullpen on May 16.
Source: Sponcihi 5/17/2017
[UPDATE 5/18 @ 5:37pm]
Yamaguchi started a Ni-gun game against Yakult at Giants Stadium today. He pitched two shutout innings. He threw thirty-five pitches, allowed one hit, walked two, and topped out at 149km/h twice.
[UPDATE 5/24 @ 9:42pm]
Yamaguchi is slated to get another Ni-gun start on May 26 against Rakuten.
Source: Nikkan Sports 5/24/2017
[UPDATE 5/26 @ 2:49pm]
Yamaguchi is expected to pitch five innings or throw about eighty pitches during his rehab start today. He will be extended to seven innings or around 120 pitches for his next rehab start. Assuming no problems, he could make the active roster in time for a start during a Nippon Ham series that begins on June 9.
Source: Nikkan Sports 5/26/2017
[UPDATE 5/27 @ 7:00pm]
Yamaguchi started a game against Ni-gun Rakuten today and tossed five shutout innings. He threw sixty-nine pitches, allowed one hit, walked one, struck out three, and topped out at 150km/h. He did not allow any hits through the first four innings.
Source: Nikkan Sports 5/27/2017