Heisman Trophy winner and college baseball standout Kyler Murray is sticking with football.

The Oklahoma quarterback and outfielder announced on Twitter Monday that he's "firmly committing mt life and time to becoming and NFL quarterback."

Murray was selected ninth overall by the Oakland Athletics in the 2018 MLB amateur draft after slashing .296/.398/.556 as an outfielder for the Sooners in 2018. But with Murray slated to start at quarterback for the Sooners, the A's allowed Murray to finish up his football career before reporting to spring training in 2019.

Filing in for former Heisman Trophy winner Baker Mayfield, Murray went on to toss 42 touchdown passes in his senior season at Oklahoma, leading the Sooners to a 12-2 record and a spot in the College Football Playoff.

Murray was slated to report to Spring Training later this month. However, Murray will skip spring training and instead focus on training for NFL Scouting Combine, which will take place in Indianapolis between Feb. 26 and March 4.

While some NFL executives are concerned about Murray's size (Oklahoma lists him as 5'11"), the 2019 quarterback class is considered weak, meaning Murray could be drafted in the first round.

When he signed with the A's last year, Murray agreed to a $4.6 million signing bonus. According to MLB reporter Jeff Passan , Murray will return $1.29 million of the $1.5 million the A's have already paid him, amd forfeit the remaining $3 million owed to him.

Numerous athletes have chosen to play both pro football and pro baseball — Bo Jackson was a Pro Bowl running back for the Raiders and appeared in an All-Star Game while playing baseball full time with the Kansas City Royals, and Deion Sanders once attempted to play sports sports professionally in the same day. However, Murray has ruled out playing both sports simultaneously, saying the off-the-field work required to play quarterback in the NFL would make playing baseball impossible.