Armour began his managerial career with the Dayton, Ohio baseball club, of which he was also the principal owner.

With the signing of Ty Cobb, the Tigers set the table for three consecutive American League pennants that followed from 1907 to 1909.

[1] At the end of August 1891, Armour signed with Oshkosh in the Wisconsin State League and played the remainder of the season there.

[1][3] In 1892, Armour appeared in 52 games, principally in right field, for the Toledo Black Pirates of the Western League.

[1][4] In 1893, Armour played for the Kansas City Blues in the Western Association and saw his batting average jump to .280 with 22 runs scored and 14 stolen bases in only 20 games.

The use of Armour, a Western Association player, in the game prompted a protest by the Duquesne club that Braddock's pennant be forfeited.

[5][6] Armour signed to play with Buffalo in January 1894,[7] but was badly injured in a coasting accident at his hometown of Homestead in February 1894.

"[10] In mid-April 1894, Armour announced that the injury, which had nearly broken his back, would prevent him from playing baseball for six weeks to two months.

After being released by Buffalo, he played in one game each for three Pennsylvania State League teams -- Easton, Scranton, and Altoona.

"[15][16] In 1897, Armour began his managerial career at age 27 as player-manager for the Dayton Old Soldiers in the Interstate League.

[27] In Armour's third year in Cleveland, the team again improved, compiling an 86-65 record as Lajoie won his second consecutive American League batting crown.

"[29] On September 8, 1904, Armour announced his resignation as manager of the Cleveland club, effective at the end of the season.

[32] Accordubg to Bill James' "Historical Baseball Abstract" Armour quite likely was the inventor of platooning while with Detroit in his use of catcher Boss Schmidt.

[36] Cobb later wrote:"To Manager Armour, my first big league boss, I cannot give too much thanks for his kindly action and his personal attention to me, my work and my welfare.

[38][39][40] The 1906 Tigers were also plagued by numerous injuries, including the loss of second baseman Germany Schaefer,[41] and the team's record slid in 1906 to 71-78.

[44] After the season ended, team owner Frank Navin alleged that Armour had been "too lenient with the players.

However, attendance declined after Swayne field was sold, and the team was required to play its games at a less convenient location during the 1910 and 1911 seasons.

In November 1911, Armour purchased the Lancaster club in the Ohio State League and took over as the team's manager.

[47] However, Armour opted not to manager the Lancaster team and instead accepted a position as a scout for the St. Louis Cardinals during the 1912 season.

The result was that I found myself moping about during the evening, apparently sore at myself, the world and everything else and then decided that if I wanted to have any pleasure in life I would have to give up trying to manage a ball club.

[49][50] On March 27, 1901, Armour was married to Ida Fulton at the home of the bride's parents in Homestead, Pennsylvania.