The Philadelphia Phillies have done \"significant work\" on Japanese pitcher Yoshinobu Yamamoto, according to a report.
Yamamoto, 25, has won NPB\'s equivalent of the Cy Young in each of the last three seasons.
He went 17-6 with a 1.16 ERA and 0.86 WHIP with 176 strikeouts in 171 innings in 24 starts this past season.