Nelson was drafted by the Cincinnati Reds in the 39th round of the 2007 Major League Baseball draft out of the Niceville High School in Niceville, Florida, but did not sign and attended the University of Alabama. In 2010, his junior year, he went 9-3 with a 4.01 ERA in 18 games. He was then drafted by the Milwaukee Brewers in the second round of the 2010 Major League Baseball draft. Nelson started the 2013 season with the Double-A Huntsville Stars. He was promoted to the Triple-A Nashville Sounds on June 5. He was promoted to the majors on September 3, made his debut on September 6, and made his first major league start on September 28. , triple-A affiliates of the Brewers, in Prior to the 2014 season, Nelson was rated the Brewers' top prospect and 96th best prospect in baseball by Baseball America. Nelson began 2014 back at Triple-A Nashville, and dominated the Pacific Coast Leagueto the tune of a 10–2 record, 1.46 ERA, and 114 strikeouts. Nelson was even named 2014 PCL Pitcher of the Year. He made one spot start for Milwaukee against the Miami Marlins due to a minor injury suffered by Yovani Gallardo on May 25, and recorded his first major league win, pitching 5 and 2/3 scoreless innings with 3 walks and 6 strikeouts. On July 10, Nelson was recalled again to join the starting rotation in place of the home run-prone Marco Estrada. He got his first career base hit during his July 17 start. Nelson sustained an injury on September 17 against the St. Louis Cardinals when Tommy Pham hit a line drive that ricocheted off his head. Nelson was able to leave the field in his own ability, and a magnetic resonance image revealed a contusion. In 2015 he had an ERA of 4.11 and shared the major league lead inhit batsmen, with 13. In 2016 he had an ERA of 4.62 and shared the major league lead in hit batsmen, with 17. On September 8, 2017, Nelson suffered an apparent shoulder injury while sliding to first base, and left the game. The next day, on September 9, it was revealed that he was diagnosed with a right rotator cuff strain and a partial anterior labrum tear, meaning that he would take no further part in any action for the remainder of the 2017 season. Nelson finished the 2017 year with a 12–6 record, 199 strikeouts, and a 3.49 ERA. On December 2, 2019, Nelson was non-tendered and became a free agent.
Los Angeles Dodgers
On January 7, 2020, Nelson signed a one-year, $1.25 million, contract with the Los Angeles Dodgers that also included an option for 2021. On July 6, it was announced that Nelson would undergo surgery on his lower back and would miss the entire season.
Scouting report
Nelson throws four pitches. He relies primarily on his sinker, fourseam fastball and slider. He also occasionally throws a change up.
Personal life
Nelson married longtime girlfriend Melissa Conway on December 10, 2016 in Nashville, Tennessee.
