Mariot pitched in the majors from 2014-16, first with the Kansas City Royals and later with the Philadelphia Phillies. He owns a 2-0 record with a 5.98 ERA and two saves at the Major League level, having pitched in 44 games out of the bullpen. 

Mariot began the 2015 season with the Royals Triple-A affiliate in Omaha but later earned a September call-up, making three relief appearances for a Kansas City team that went on to win the World Series. The Royals designated Mariot for assignment following the season, with the Phillies claiming him off waivers just ten days later. He went on to pitch in 25 games out of the Philadelphia bullpen in 2016, finishing four games and earning a pair of saves while allowing only 18 hits in 21.2 innings.

After spending the entirety of the 2017 season with Triple-A Lehigh Valley, Mariot split 2018 between the San Diego Padres and Royals minor league systems. He signed with the Atlantic League’s Sugar Land Skeeters late in the 2018 season and helped the club to a league title, picking up the victory in Game One of the Championship Series against the Long Island Ducks.

Mariot re-joined the Skeeters to begin 2019, and had his contract purchased by the Tijuana Toros of the Mexican League. He finished out the season with the Tecolotes de los Dos Laredos.

Mariot played his high school baseball at local powerhouse Southlake Carroll after transferring from El Camino Real High School in Woodland Hills, California. The 6’0, 195-pounder went on to play three seasons collegiately at the University of Nebraska, eventually developing into a weekend starter for the Cornhuskers. He was drafted by the Royals in the 8th round of the 2010 MLB Draft, and spent four seasons in their minor league system before making his MLB debut in 2014.