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| Name: | John O'Brien |
| Given name: | John Joseph |
| Birth place: | St. John, NB, CAN |
| Birthday: | 7/13/1866 |
| Height: | 69 inches |
| Weight: | 175 lbs |
| Batting: | Left-handed |
| Throwing: | Right-handed |
| Age/Age at time of death: | 46 |
| Year | Team Name | Batting Statistics | Pitching Statistics | Fielding Statistics |
|---|---|---|---|---|
| 1891 | Brooklyn Grooms | Hits: 4 At Bats: 41 HR: 0 RBI: 2 | Wins: 2 Losses: 10 Total Games: 13 Strikeouts: 32 Shutouts: 0 | Position: 3B Errors: 8 Double Plays: 2 Assists: 21 |
| 1893 | Chicago Colts | Hits: 6 At Bats: 26 HR: 0 RBI: 2 | Wins: 2 Losses: 4 Total Games: 7 Strikeouts: 6 Shutouts: 0 | Position: P Errors: 4 Double Plays: 1 Assists: 14 |
| 1895 | Louisville Colonels | Hits: 1 At Bats: 3 HR: 0 RBI: 0 | Wins: 0 Losses: 1 Total Games: 1 Strikeouts: 3 Shutouts: 0 | Position: P Errors: 0 Double Plays: 0 Assists: 3 |
| 1896 | Louisville Colonels | Hits: 12 At Bats: 63 HR: 0 RBI: 7 | Wins: 8 Losses: 8 Total Games: 25 Strikeouts: 37 Shutouts: 0 | Position: P Errors: 4 Double Plays: 0 Assists: 34 |
| 1896 | Washington Senators | Hits: 12 At Bats: 63 HR: 0 RBI: 7 | Wins: 8 Losses: 8 Total Games: 25 Strikeouts: 37 Shutouts: 0 | Position: P Errors: 4 Double Plays: 0 Assists: 34 |
| 1897 | Washington Senators | Hits: 3 At Bats: 10 HR: 0 RBI: 0 | Wins: 4 Losses: 4 Total Games: 11 Strikeouts: 19 Shutouts: 0 | Position: 2B Errors: 1 Double Plays: 0 Assists: 7 |
| 1899 | Baltimore Orioles | Hits: 118 At Bats: 439 HR: 4 RBI: 92 | Wins: 6 Losses: 4 Total Games: 12 Strikeouts: 26 Shutouts: 0 | Position: 1B Errors: 8 Double Plays: 25 Assists: 24 |
| 1899 | Pittsburgh Pirates | Hits: 118 At Bats: 439 HR: 4 RBI: 92 | Wins: 6 Losses: 4 Total Games: 12 Strikeouts: 26 Shutouts: 0 | Position: 1B Errors: 8 Double Plays: 25 Assists: 24 |