Samuel Johnathan Tuivailala (born October 19, 1992) is an American former professional baseball pitcher.

He played in Major League Baseball (MLB) for the St. Louis Cardinals and Seattle Mariners.

He appeared in 11 games and had a 4.15 earned run average (ERA) in 13 innings with 23 strikeouts, but issued 13 walks.

He also co-led the PCL in games finished (23) and tied for third-most with 11 saves, converting all 11 opportunities.

[18] In 2019, Tuivailala made 23 appearances for Seattle, recording a strong 2.35 ERA with 27 strikeouts in 23.0 innings of work.

[19] Tuivailala did not appear for the team in spring training the following year due to a right shoulder impingement.

[20] On April 18, 2023, after several years of inactivity, Tuivailala signed with the Acereros de Monclova of the Mexican League.

On September 29, 2023, Tuivailala announced that he had been selected to participate in MLB's Diversity Pipeline Scout & Coaching Development Program.