Jack O'Brien (o'brija01)
From BR Bullpen
John K. O'Brien
born John K. Bryne
- Bats Right, Throws Right
- Height 5' 10", Weight 184 lb.
- Debut May 2, 1882
- Final Game September 16, 1890
- Born June 12, 1860 in Philadelphia, PA USA
- Died November 20, 1910 in Philadelphia, PA USA
 Biographical Information
Jack O'Brien, born John Byrne, played eight seasons in the majors and was an above-average hitter, which is surprising since many of his games were at catcher, a position which took a toll on players of the time.
He spent most of his major league career with the A's, leaving only to play once with Brooklyn and once with Baltimore. He was always primarily a catcher except in his last year, 1890, when he mostly played first base. His bat was good enough that he stayed in the lineup, playing every position on the diamond except for pitcher.
His rookie year was his best with the bat, as he ranked in the top five in the league in batting average and OBP, and was sixth in SLG. Although mainly playing catcher, he was by far the best hitter on the team, which finished over .500.
After the majors O'Brien played in the Western Association.
He is not to be confused with another Jack O'Brien nor with a number of players named John or Johnny O'Brien.