(SportsNetwork.com) - Major League Baseball teams could begin negotiating with standout Japanese pitcher Masahiro Tanaka on Thursday, according to a league spokesman.

Tanaka's Japanese club said Wednesday it would make the right-hander available through the posting system after initially denying him the opportunity to play in the majors.

MLB teams were told the 30-day period to sign Tanaka began Thursday at 8 a.m., league spokesman Mike Teevan confirmed to SportsNetwork.com.

Under new rules set this offseason, a posting fee cap was set at $20 million -- the amount teams must commit to negotiate with a player during the 30-day window.

If a contract for Tanaka is worked out, the MLB team that signs him will need to pay the Rakuten Golden Eagles $20 million. Teams that do not secure a deal will be refunded their money.

Tanaka, who is still under contract with Rakuten for two more years, went 24-0 last season with a 1.27 earned-run average in 28 games, helping lead the team to the Japan Series title.

The 25-year-old is 99-35 with a 2.30 ERA and 1,238 strikeouts in 175 games for Rakuten since 2007. He has 53 complete games, including 18 shutouts.

The New York Yankees, Boston Red Sox and Los Angeles Dodgers are among the clubs reportedly prepared to bid for Tanaka.

The new posting rules were put in place to avoid situations like the one that led to the Texas Rangers signing pitcher Yu Darvish away from the Hokkaido Nippon Ham Fighters with a posting fee of $51.7 million.

Before the $20 million limit took effect, the team that offered the highest posting fee under a blind bidding system could negotiate for 30 days with a specific club. If a deal couldn't be reached by the deadline, the player would remain in Japan for another season.

Instead of one team negotiating with the player under the former system, each team that pays the posting fee can try to work out a contract.