Cleveland Indians Nelson was selected by the
Cleveland Indians in the 15th round of the
2017 Major League Baseball draft. After signing with Cleveland, Nelson made his professional debut with the
Mahoning Valley Scrappers where he went 3–2 with a 2.48 ERA over 29 innings pitched in relief. Over innings pitched between the two clubs, he compiled a 6–1 record and a 1.58 ERA, striking out 67 and walking nine. Nelson began 2019 with Lynchburg before being promoted to the
Akron RubberDucks in May where he earned
Eastern League All-Star honors. In August, he was promoted to the
Columbus Clippers, with whom he finished the year. Over 42 games with the three teams, he went 4–4 with a 2.28 ERA and 69 strikeouts over innings. The Indians selected Nelson's contract on September 9, 2020. He made his major league debut the next day against the
Kansas City Royals, giving up four
earned runs over of an inning; this was his only appearance for Cleveland for the 2020 season. In 2021, Nelson pitched innings in relief for the Indians, giving up ten runs, striking out eight, and walking eight. While not with Cleveland, he pitched for the Clippers (now members of the
Triple-A East) with whom he went 0–1 with a 6.66 ERA, twenty walks, and thirty strikeouts over innings. Nelson was
designated for assignment by the newly named Cleveland Guardians on November 19, 2021.
Arizona Diamondbacks Nelson was claimed off waivers by the
Arizona Diamondbacks on November 24, 2021. He was assigned to the Triple-A
Reno Aces to begin the 2022 season, and was recalled on April 10, 2022. Nelson made a career-high 43 appearances, posting a 2–1 record and 2.19 ERA with 30 strikeouts in 37 innings pitched. Nelson was initially optioned to Triple-A Reno to begin the 2023 season. However, after
Joe Mantiply suffered an injury, he was placed in the Opening Day bullpen. In 68 appearances for the Diamondbacks, Nelson registered a 7–4 record and 4.18 ERA with 67 strikeouts across 56 innings pitched. In 2024, Nelson posted a 4.22 ERA in 11 games before he was placed on the injured list with left shoulder inflammation on April 23, 2024. He was transferred to the 60–day injured list on April 30. The same day, it was announced that Nelson would undergo surgery for
thoracic outlet syndrome. Nelson was optioned to Triple-A Reno to begin the 2025 season, but struggled to an 8.47 ERA with 12 strikeouts over 17 innings of work. Nelson was
designated for assignment by the Diamondbacks on July 2, 2025. He cleared waivers and was sent outright to Reno on July 6. On August 1, the Diamondbacks added Nelson back to their active roster. In three appearances for Arizona, he struggled to a 9.00 ERA with two strikeouts and one
save over two innings of work. On November 6, Nelson was removed from the 40-man roster and sent outright to Reno. He elected free agency the same day.
Atlanta Braves On February 25, 2026, Nelson signed a minor league contract with the
Atlanta Braves organization. He was released by the Braves on March 21. ==References==