If it's a choice between Okamoto or Murakami, I'm OK with Okamoto. A good bat and good glove -- with less Ks -- helps the Red Sox in more ways than just the big fly.
I don't feel good about this, but I can't help comparing any potential hitter from Japan to Yoshida. It's more about their league compared to the long seasons of the majors, and not just a WBC tournament all over the planet in March (where Masa rocked last time out).
In 11 pro seasons in Japan, Kazuma Okamoto had a .277 batting average, with a .361 OBP/.521 SLUG/.882 OPS. He struck out 796 times with 481 walks.
In 7 pro seasons in Japan, Masataka Yoshida had a .327 batting average, with a .421 OBP/.539 SLUG/.960 OPS. He had only 300 Ks to 421 BBs.
Masa hit over 20 homers four times, and in his last three seasons had twice as many walks as strikeouts. Kaz hit over 30 HRs five straight years, but not his last two... there must have been some injuries then (buyer beware?).
Bottom line: Boston is hesitant to play Yoshida in the field; the Sox cannot miss on recruiting another guy longterm if they're not sure he can play defense at the big league level.