James Lorin Nelson (July 4, 1947 – August 22, 2004) was an American right-handed pitcher in Major League Baseball for the Pittsburgh Pirates in 1970 and 1971.

He relieved Gene Garber in the fifth inning of a game at Forbes Field against the San Francisco Giants, struck out Willie Mays, and got Willie McCovey to hit into a double play; he finished that appearance with three perfect innings pitched and four strikeouts, and hit a single in his only plate appearance.

[3] Nelson also was the last Pirate pitcher to win his first 3 career starts until Gerrit Cole matched the feat in 2013.

[4] Nelson also was the starting and winning pitcher in the final game played at Forbes Field on June 28, 1970.

[6] In July, he was demoted to the minor leagues, but refused to report to his minor-league team.