Born in Pardeeville, Wisconsin in 1876, Claude Judson Elliott's ten-year baseball career included stops in Detroit of the Western League; Milwaukee, Louisville, and Indianapolis of the American Association; and Cincinnati and New York of the National League. Before breaking into the majors, he pitched in several low-level circuits, including the Wisconsin State League and the Michigan League. In 1899, he appeared in 1 game for Rockford (then an affiliate in the Western Association) before breaking an ankle. After sitting out the following season, he returned to Rockford, then a member of the newly formed Three Eye.

A few notes on the 1901 season: The Rockford Red Sox, though they also included future big league outfielder Davy Jones, ended the season in fourth place (57-55). Elliott was not the league's only pitching prospect. Future Cooperstown inductee Mordecai "Three Finger" Brown went 23-8 for first-place Terre Haute. During the 1901 season, the Rockford Daily Register-Gazette referred to Elliott as the "Big He," though during his career he was also called "Chaucer" and "Old Pardee." The Cedar Rapids Republican, in the flatulent prose of the day, described Elliott forthwith: "With a magnificent physique, and an avoirdupois that is weighty, perfect confidence and superb control, he is the beau ideal box artist." Rockford skipper Hugh Nicol had played professional ball during the 1880s, appearing in a combined 888 games for the Chicago White Stockings (forerunner to the Cubs), St. Louis Browns, and Cincinnati Red Stockings.

At the end of the 1901 Three-I season, Claude Elliott "jumped" to Milwaukee of the American League. In 1902, the Brewers franchise and roster were transferred to St. Louis. It remains unclear why Elliott did not play for St. Louis. Did the Browns find his abilities wanting? Or did Elliott wish to remain in Milwaukee, since it was close to his hometown? Regardless, Elliott stayed in Milwaukee to play for the city's American Association club. In two seasons he won 35 and lost 27, and in 1903 he led the league in strikeouts (228).

In 1904, Cincinnati purchased Elliott, and he appeared in 9 games, going 3-1 with a 2.97 ERA. That same season, the Reds moved Elliott to the Giants. At that time, John McGraw of the New York Giants and Clark Griffith of the New York Highlanders were experimenting with relief pitching, then a radical concept with more detractors than supporters. Before the acceptance of relief as an essential specialty position, workhorse starting pitchers bailed out lesser teammates. In 1904, the complete-game percentage in both leagues hovered around 90 percent. The following season, the percentage fell 10 points in the A.L. and 7 points in the N.L. This significant decline was attributable to the then-radical schemes of McGraw and Griffith, two of the sport's greatest adversaries.

McGraw rescued Elliott from comparative obscurity by converting "Big He" into the big league's first relief specialist, and baseball would never be the same. Author John Thorn highlighted Elliott's 1905 season in The Relief Pitcher: Baseball's New Hero (New York: Dutton, 1979): "Claude pitched only ten games for Mr. McGraw in 1905, of which two were route-going starts. The other eight outings were as rescue pitcher--the preferred appellation at the time--and Elliott proved up to the task. Though he neither won nor lost, he saved six games and, in 25 innings of relief work, notched a respectable ERA of 2.88. Yet when 1906 rolled around, Elliott was gone, never to pitch in the big time again. Like the man whose record he surpassed [Boston's Jack Manning in 1876], Claude Elliott was a comet, shining brightly but briefly."

Since relief pitching was still in its infancy, Elliott did not make an appearance in the 1905 World Series. The Giants defeated Connie Mack's Philadelphia Athletics 4 games to 1. Christy Mathewson completed and won 3 games, and Joe McGinnity went 1-1. Red Ames, a righthander who won 22 games in the regular season, pitched the one and only inning of relief work. 

After his brief stint in New York, Elliott returned to the American Association, playing for Louisville and (briefly) Indianapolis. He then spent several years as a minor league umpire in Illinois, Minnesota, and Wisconsin. Elliott died on June 21, 1923 in his hometown of Pardeeville. 

Born and raised in St. Louis, Elliott dominated the 1919 city championship series. Soon afterward, Browns scout Charlie Barrett signed the 19-year old lefthander to a Major League contract. After serving as the Browns batting practice pitcher, the St. Louis club shipped Elliott to the Terre Haute Tots of the Three Eye. In 1921 and 1922, Elliott appeared in 75 games, winning 35 and losing 22 (during that two-year span, teammate and future big leaguer Charlie Root went 24-21). In 1922, Elliott led the Three-I in strikeouts (214). That November, he married Elsie Carpenter of Terre Haute, and shortly thereafter the couple made the city their permanent residence.

During Elliott's first two years in Terre Haute, the Tots were led by Bob Coleman, the greatest manager in Three Eye history. Coleman left the league after 1923 and would not return until 1928. He spent 1923 through 1925 with San Antonio of the Texas League, and 1927 with Knoxville of the Sally League. In 1923, Elliott, still pitching for Terre Haute, won 13 and lost 7, and again led the Class B loop in strikeouts (154). He also pitched 1 inning for the American League Browns, giving up 1 hit and 3 earned runs. The following season, Elliott joined his former manager in San Antonio, appearing in 12 games, winning 2 and losing 2 with a 4.14 ERA. With Terre Haute in the middle of a pennant race, Ray Whitcraft, the Tots new skipper, brought fan favorite Elliott back to his former league. The burly lefthander then won five games in the final weeks of the Three-I season, including the pennant clincher against the Danville Veterans. 

In 1925, Elliott enjoyed his second "cup of coffee," losing 2 games for Brooklyn in ten-plus innings of work. The Robins then shipped Elliott back to Terre Haute for his fifth and final season in the Three-I. Back in familiar surroundings, he enjoyed his finest professional season to date, leading the league in wins (25) and ERA (3.03). Despite the impressive showing, the Robins believed the lefthander was yet unprepared for the rigors of the National League. So instead of Brooklyn, Elliott found himself playing in Seattle of the Pacific Coast League. There he started 48 games, winning 26 and losing 20 for a seventh-place club. In 367 innings of work, he finished with a 2.55 ERA. "My best baseball feat," recalled Elliott, "was winning ten straight for Seattle of the Coast League. I lost the eleventh, but it was the best pitched game of all."

Based on this impressive showing in the well-regarded P.C.L., Elliott earned a third and final promotion to the big leagues. From 1927 through 1930, Elliott appeared in 122 games for Brooklyn, winning 26 and losing 36. The Robins then dealt him to the Phillies in a five-player trade that included Lefty O'Doul. In 1931, Jumbo Elliott led the National League in wins (19) and games (52) for sixth-place Philadelphia. He completed 12 of his 30 starts, ending the season with a 4.27 ERA. The following year he went 11-10 in 22 starts, but he would win only 7 more games over the 1933 and 1934 seasons. He ended his career with 63 wins and 74 defeats and an ERA of 4.24. 

Elliott returned to Terre Haute in 1935, and for a while he managed a local tire company and played semi-pro ball. In 1941, he became a deputy sheriff and four years later he rose to chief deputy. In 1966, he ran for county sheriff, losing to former NBA All-Star Clyde Lovellette. Jumbo Jim Elliott died on January 7, 1970 at the age of 69.