What is Pro Mahjong?

If you’ve ever sat around a mahjong table with friends, you probably know the game as a casual pastime—a mix of luck, tiles clacking together, and maybe a little friendly rivalry. But over the last two decades, riichi mahjong has quietly transformed from a niche Japanese parlor game into a serious, global competitive sport.

With the establishment of the US Pro Mahjong League in 2010, and the World Riichi Championship in 2014, this transformation came to the United States. By 2017, USPML was hosting the 2nd WRC Championship in Las Vegas in July 2017 a tradition which has repeated every 3 years since in cities like Paris, Vienna, and Tokyo. New York City is set to host the next WRC in 2028.

However, this new international scene proved difficult to integrate with the existing pro Japanese system. Unlike sports with a single governing body, professional riichi mahjong in Japan is organized into multiple leagues and associations, each with its own membership system, ranking ladder, and tournaments.

Many of these groups are independent, but they interact through shared events and cross-participation in high-profile competitions.

1. Saikouisen Nihon Pro Mahjong Association (最高位戦日本プロ麻雀協会)

• Founded: 1981
• Focus: Considered one of the oldest and most established pro groups. Known for emphasizing strategy and depth of play.
• Structure: Players progress through ranking classes (C → B → A → Saikouisen title league).
• Notable Event: Saikouisen Title Match, one of the major professional titles in Japan.
• International Link: Partner of Saikouisen USA, extending professional structures abroad.

2. Japan Professional Mahjong League (日本プロ麻雀連盟, JPML)

• Founded: 1981
• Focus: One of the largest and most visible leagues, with a strong media presence.
• Structure: Players compete in ranked classes; top players vie for major league titles.
• Key Titles:
  • Honketsusen (本戦選) – Main League
  • Professional Mahjong League Championship
• Media: Publishes strategy books and streams games widely.

3. Japan Professional Mahjong Association (日本プロ麻雀協会, JPMA)

• Founded: 2001
• Focus: A newer league, formed partly to modernize and expand professional mahjong.
• Structure: Class rankings and tournament play.
• Notable for: Active participation in online platforms like Tenhou and Niconico to reach new audiences.

4. RMU (Real Mahjong Unit / 競技麻雀団体RMU)

• Founded: 2007 by prominent pro Masayuki Katayama and others.
• Focus: More experimental, with flexible tournament structures.
• Titles: Runs the R1 League and other internal ranking competitions.

While these traditional leagues preserve depth, history, and grassroots talent development in Japan, they proved a major obstacle to integrating global competitors with the Japanese system.

How do players from other countries assess their readiness to compete with Japanese pros? How can international events slot themselves into such a complex system of tournaments? Is it fair for longstanding organizations to have to change their local rule set to make way for an international standard?

These questions took many years to navigate, and were only half of the puzzle. The American domestic side was also complex, with most venues, tournaments, and leagues being organized by independent local clubs.

Leaders of mahjong organizations worldwide worked together for many years to find a solution to these problems, which lead to the creation of the American Riichi Association, the M League, which consolidates all four pro organizations in Japan into a single televised competition, and the new WRC 2025 international rule set.

By consolidating organizations worldwide into standardized national and international qualification systems, we now have a foundation with which to build a vibrant and truly global competitive riichi scene.

So much to say that the 2020s are set to be a decade of unprecedented growth for the amateur and professional riichi mahjong scene.

While many obstacles still exist between American players and international competition, we now have a unified national qualification system and two pro organizations with allocated spots in the World Riichi Championship: WR Pro and Saikouisen USA.

The 2025 Season: League Play and Live Matches

League Structure and Venue

The 2025 season of the Saikouisen USA League is being held in collaboration with Los Angeles Pride of Mahjong (LAPOM) a.k.a. Mahjong Stars in California, with streamed games available on the Saikouisen USA Youtube channel.

League days are scheduled as follows:

• Day 1: July 13
• Day 2: August 3
• Day 3: August 31
• Day 4: October 5
• Day 5: November 2
• Day 6 (Finals): December 7

League streams are a rare opportunity to spectate pro mahjong with full English graphics and commentary.

Want to become a mahjong pro?

Start your journey with Mass Riichi!

Our organization exists to raise the bar of riichi mahjong in Massachusetts and the USA.

We believe in a “deep and wide” approach to competitive development, meaning that we don’t only invest in deepening the skills of our existing player base, but also to widening the overall talent pool by bringing in new players, integrating them into a supportive and welcoming community, and then inviting them to engage in the competitive scene when they are ready.

We are proud collaborators of ARA and the WRC, who are passionate about training up the next generation of global all-star players! We offer weekly practice sessions, tournaments, educational lectures, group coaching, and one-on-one mentorship, all at zero cost.

To join our club and start your climb to the pro leagues, sign up for our newsletter , join our Discord, and check our Google calendar to locate your nearest Open Play Practice Meet.

Whether your goal is the WRC or just to make the final table at our Boston Locals practice tournament, we want to help you achieve your competitive goals.