Johnny O'Brien was traded 2 times:

Acquired: $0.00 - Sent: $0.00 = $0.00
Acquired: 1201 G - Sent: 187 G = 1014 Games
Acquired: 3448 PA - Sent: 644 PA = 2804 Plate Appearances
Acquired: 0.0 - Sent: 6.0 = -6.0 Innings Pitched
Acquired: $0.00 - Sent: $74,500.00 = $-74,500.00
Acquired: 3643 G - Sent: 2824 G = 819 Games
Acquired: 10419 PA - Sent: 7602 PA = 2817 Plate Appearances
Acquired: 11796.0 - Sent: 7676.0 = 4120.0 Innings Pitched
Transactions current as of 2021 season. See an issue with this player? Please report it.

Transaction and player information was obtained from Retrosheet.

View the site on Github.