JK
1944–1956 · P

Jim Konstanty

6' 1", 202 lbs·Lived to 59·Bats R / Throws R
MVPAll-Star
The Almanac's Take

The first relief pitcher to win an MVP award, Konstanty revolutionized how baseball viewed closers in 1950 when he appeared in 74 games for the Phillies' "Whiz Kids" pennant winners. His 16-7 record and 2.66 ERA that season came almost entirely out of the bullpen — a radical departure from the era's starter-heavy approach.

That peak season produced an otherworldly 442 ERA+, meaning he was more than four times better than league average. Even more remarkably, Philadelphia trusted him to start Game 1 of the World Series against the Yankees, the ultimate validation of his value.

Konstanty's career 146 ERA+ across 13 seasons proves he wasn't just a one-year wonder. He threw a devastating palm ball that kept hitters off balance, finishing with a 3.46 ERA in 433 appearances. His MVP trophy opened the door for relief aces like Dennis Eckersley and Rollie Fingers to follow.

Career Highs
2.32
Best ERA · 1955
16
Most W · 1950
56
Most K · 1950
1.039
Best WHIP · 1950
Career Arc · ERA
11 seasons
Statistical Comps

Career · Hitting

11 seasons
YearTeamGABHRRBIAVGOPSOPS+
1944CIN203402.294
1946BSN10200.000
1948PHI6300.000
1949PHI531701.176
1950PHI743703.108
1951PHI581900.158
1952PHI421402.071
1953PHI485005.220
1954PHI421600.000.000
1955NYY45800.125.347
1956NYY35201.000.000
Career433202014.163

Career · Pitching

11 seasons
YearTeamGIPWLERAERA+SOWHIP
1944CIN20112.7642.80128191.296
1946BSN1015.3015.286891.565
1948PHI69.7100.9344270.931
1949PHI5397.0953.25127431.309
1950PHI74152.01672.66164561.039
1951PHI58115.74114.05100271.366
1952PHI4280.0533.9494161.350
1953PHI48170.714104.4393451.406
1954PHI4268.7343.01130141.325
1955NYY4573.7722.32172191.249
1956STL3550.3114.6585131.450
Career433945.86648268
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Jim Konstanty Stats & Analysis | The Almanac