1899 St. Louis Perfectos season

The 1899 St. Louis Perfectos season was the team's 18th season in St. Louis, Missouri and their eighth season in the National League. The Perfectos went 84–67 during the season and finished fifth in the National League.

This was the team's only season in which they were named the Perfectos. The Robison brothers, who had just bought the team from original owner Chris von der Ahe, changed the colors to red, the name of the team to Perfectos, and the name of the ballpark to League Park. The red color proved so popular that fans and sportswriters began referring to the team by the shade of red, cardinal. The next season, the team officially became the Cardinals.

The team benefited from many players who were transferred to the team from the Cleveland Spiders, which were also owned by the Robison brothers. This led to the Spiders compiling the worst season in MLB history, losing 134 games. However, the Perfectos wound up finishing only fifth. The pennant-winning Brooklyn Superbas, who finished 18½ games ahead of St. Louis, benefited from a similar arrangement, as Brooklyn's owners also owned the Baltimore Orioles, allowing them to also transfer their better players to one team. After the 1899 season, such arrangements were outlawed in the National League, and both the Spiders and Orioles were among four teams eliminated from the league.

Notable transactions

 * March 29, 1899: Jack O'Connor was assigned to the Perfectos by the Cleveland Spiders.

Starters by position
''Note: Pos = Position; G = Games played; AB = At bats; H = Hits; Avg. = Batting average; HR = Home runs; RBI = Runs batted in''

Other batters
''Note: G = Games played; AB = At bats; H = Hits; Avg. = Batting average; HR = Home runs; RBI = Runs batted in''

Starting pitchers
Note: G = Games pitched; IP = Innings pitched; W = Wins; L = Losses; ERA = Earned run average; SO = Strikeouts

Other pitchers
Note: G = Games pitched; IP = Innings pitched; W = Wins; L = Losses; ERA = Earned run average; SO = Strikeouts

Relief pitchers
Note: G = Games pitched; W = Wins; L = Losses; SV = Saves; ERA = Earned run average; SO = Strikeouts