A preliminary 50-man roster for the World Baseball Classic, an international tournament, was selected and announced on Thursday by the Korea Baseball Organization.

The roster includes five Major League Baseball players: Choo Shin-soo of the Texas Rangers, Kang Jung-ho of the Pittsburgh Pirates, Kim Hyun-soo of the Baltimore Orioles, Lee Dae-ho of the Seattle Mariners and Park Byung-ho of the Minnesota Twins.

Oh Seung-hwan of the St. Louis Cardinals was not included in the roster. The KBO explained that the pitcher was eliminated from selection due to a gambling scandal. Oh was slapped with fines early this year for illegally gambling in Macau in 2014.

But some critics questioned the KBO's selection criteria, because Lim Chang-yong of the Kia Tigers, who was fined along with Oh for the same offense, made the roster.

"Lim has been banned for half the regular season, but Oh has yet to be punished as he is in the U.S.," said the KBO's Yang Hae-young.

Changes to the roster can still be made, as it is only provisional.