Famer Joe McGinnity was once paid $500 by a semi-professional team to pitch against the Philadelphia Giants. After seven scoreless innings, Monroe came to bat and pointed his bat at McGinnity, taunting him. McGinnity knocked Monroe down with his next pitch, but Monroe kept up the taunting. He then bet McGinnity $500 that he'd hit a home run. The pitcher accepted the bet and fired a fastball, which Monroe hit for a home run which would ultimately win the game for the Giants. Monroe continued his taunting by running the bases backward. In 1906, Monroe played part of the season for the Philadelphia Giants, then moved to the Brooklyn Royal Giants, where he played third base until 1908 and second base from 1909 to 1910. Holway lists his 1906 batting average as .500, but without indicating how many at bats were recorded; his 1909 his batting record was listed as 6 for 8 (.750), and in 1910 it was .171. The Royal Giants were the eastern champions in 1910. A somewhat more complete statistical record comes during this period from his play in the Cuban League during the winters of 1906–1907 and 1907–1908, and from series played in Cuba in the fall of 1908. During 1906–1907, in 14 games he hit 18 for 51 (.353) with a triple and a home run (.451 slugging percentage) and 4 walks and 3 times hit by pitch (.431 on-base percentage). The following winter, he played 16 games and went 23 for 72 (.319) with two doubles and a triple (.375 slugging). Then, in the fall of 1908 the Royal Giants toured Cuba, playing against Habana and Almendares, the top teams in Cuba. Monroe played 15 games and went 13 for 56 (.232) with one triple and three walks. During the same tour, he participated in a series against the major league Cincinnati Reds. In two games he went 3 for 8 (.375) with three runs scored and one walk. Sportswriter Harry Daniels named Monroe to his 1909 "All American Team" saying "the great, fastest man in base ball, and the most wonderful base runner for the past ten years; also strong at bat." In 1911, Monroe moved to the Chicago American Giants, which were the preeminent team of that era and one of the great Negro league teams of all time. His first season, he played second base and hit cleanup behind Pete