A computer programmed to play "shogi," also known as Japanese chess, defeated an active professional player in a public match for the first time ever Saturday.

Shinichi Sato, 30, lost to the Ponanza program, developed by Issei Yamamoto, in a Shogi Master Versus Machine Match.

In 2012, the late Kunio Yonenaga, then a retired pro, was beaten by Bonkuras, written by a programmer at Fujitsu Laboratories Ltd. But an active professional player had never lost to a computer before Saturday.

Saturday's game was the second in a team contest that pits Sato and four other pros against five programs that won the top places at last year's World Computer Shogi Championship.

Playing without handicaps, Sato had the upper hand until the middle of the game, when he began making mistakes.

The first of the five games at this year's competition was won by shogi pro Koru Abe against a different program.

The third episode of the contest is set for April 6.