How do you improve? Roki Sasaki is trying to find out.

In his first start since throwing the first perfect game in professional baseball in 1994, Sasaki almost did it again for the Marines, but he was pulled after eight perfect frames in a loss to the Hokkaido Nippon Ham Fighters on Sunday.

He was pulled from the game after throwing more than 100 pitches. He was taken out after he struck out the side in the eighth, with his pitches still reaching 101 mph.

Sasaki has not allowed an opposing hitter to reach base in 52 plate appearances.

Through four starts, Sasaki has a 1.16 ERA, 56 strikeouts and has allowed seven hits and two walks.

Chusei Mannami, whose game-winning home run -- the Fighters only hit of the game -- came in the 10thinning off the third Marines pitcher, said that Sasaki is too tough. Forget about it.

In his last start, Sasaki tied an NPB record with 19 strikeouts against the Orix Buffaloes as he completed just the 16th perfect game in league history. He set a Japanese pro baseball record for strikeouts in a row.

Sasaki rose to prominence as a high school pitcher thanks to his high-velocity fastball, which drew interest from Major League Baseball teams before he signed with Chiba Lotte at the age of 18.