John O'Brien was traded 2 times:

Acquired: $0.00 - Sent: $0.00 = $0.00
Acquired: 153 G - Sent: 159 G = -6 Games
Acquired: 636 - Sent: 662 = -26 Plate Appearances
Acquired: 0.0 - Sent: 0.0 = 0.0 Innings Pitched
Acquired: $0.00 - Sent: $5,000.00 = $-5,000.00
Acquired: 3182 G - Sent: 1271 G = 1911 Games
Acquired: 12859 PA - Sent: 4723 PA = 8136 Plate Appearances
Acquired: 797.0 - Sent: 1693.0 = -896.0 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.

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