During his MLB career, Leonard has allowed 3,304 base knocks and he has 1,170 strikeouts in 3,218 innings. He has surrendered a total of 1,162 earned runs while earning a WHIP of 1.256 and a FIP of 3.3. His K/BB ratio is 1.59 and he has faced 13,487 batters during his MLB career. Leonard (191-181 career win-loss record) has earned a 3.25 earned run average while allowing 9.2 hits per 9 innings.
Dutch Leonard Stats
| Year | Team | G | IP | W | L | WHIP | ERA | H | BB | SO | FIP | SV | GS | HR | ER | R | BF | SO/W | H/9 | SO/9 |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Career | 640 | 3218.1 | 191 | 181 | 1.256 | 3.25 | 3,304 | 737 | 1,170 | 3.33 | 45 | 375 | 158 | 1,162 | 1,432 | 13,487 | 1.59 | 9.2 | 3.3 | |
| 1953 | CHC | 45 | 62.2 | 2 | 3 | 1.532 | 4.60 | 72 | 24 | 27 | 4.80 | 9 | 0 | 9 | 32 | 34 | 276 | 1.13 | 10.3 | 3.9 |
| 1952 | CHC | 45 | 66.2 | 2 | 2 | 1.200 | 2.16 | 56 | 24 | 37 | 3.08 | 11 | 0 | 3 | 16 | 18 | 282 | 1.54 | 7.6 | 5.0 |
| 1951 | CHC | 41 | 81.2 | 10 | 6 | 1.188 | 2.64 | 69 | 28 | 30 | 3.32 | 3 | 1 | 3 | 24 | 30 | 337 | 1.07 | 7.6 | 3.3 |
| 1950 | CHC | 35 | 74.0 | 5 | 1 | 1.311 | 3.77 | 70 | 27 | 28 | 4.23 | 6 | 1 | 7 | 31 | 41 | 318 | 1.04 | 8.5 | 3.4 |
| 1949 | CHC | 33 | 180.0 | 7 | 16 | 1.339 | 4.15 | 198 | 43 | 83 | 2.71 | 0 | 28 | 4 | 83 | 94 | 788 | 1.93 | 9.9 | 4.2 |
| 1948 | PHI | 34 | 225.2 | 12 | 17 | 1.241 | 2.51 | 226 | 54 | 92 | 3.23 | 0 | 30 | 9 | 63 | 85 | 920 | 1.70 | 9.0 | 3.7 |
| 1947 | PHI | 32 | 235.0 | 17 | 12 | 1.196 | 2.68 | 224 | 57 | 103 | 3.32 | 0 | 29 | 14 | 70 | 86 | 943 | 1.81 | 8.6 | 3.9 |
| 1946 | WSH | 26 | 161.2 | 10 | 10 | 1.348 | 3.56 | 182 | 36 | 62 | 3.28 | 0 | 23 | 9 | 64 | 85 | 695 | 1.72 | 10.1 | 3.5 |
| 1945 | WSH | 31 | 216.0 | 17 | 7 | 1.125 | 2.13 | 208 | 35 | 96 | 2.62 | 1 | 29 | 5 | 51 | 72 | 885 | 2.74 | 8.7 | 4.0 |
| 1944 | WSH | 32 | 229.1 | 14 | 14 | 1.129 | 3.06 | 222 | 37 | 62 | 3.11 | 0 | 31 | 8 | 78 | 97 | 936 | 1.68 | 8.7 | 2.4 |
| 1943 | WSH | 31 | 219.2 | 11 | 13 | 1.202 | 3.28 | 218 | 46 | 51 | 3.41 | 1 | 30 | 9 | 80 | 96 | 912 | 1.11 | 8.9 | 2.1 |
| 1942 | WSH | 6 | 35.0 | 2 | 2 | 0.943 | 4.11 | 28 | 5 | 15 | 2.01 | 0 | 5 | 1 | 16 | 16 | 138 | 3.00 | 7.2 | 3.9 |
| 1941 | WSH | 34 | 256.0 | 18 | 13 | 1.270 | 3.45 | 271 | 54 | 91 | 2.59 | 0 | 33 | 6 | 98 | 117 | 1,073 | 1.69 | 9.5 | 3.2 |
| 1940 | WSH | 35 | 289.0 | 14 | 19 | 1.405 | 3.49 | 328 | 78 | 124 | 3.28 | 0 | 35 | 19 | 112 | 136 | 1,245 | 1.59 | 10.2 | 3.9 |
| 1939 | WSH | 34 | 269.1 | 20 | 8 | 1.233 | 3.54 | 273 | 59 | 88 | 3.42 | 0 | 34 | 16 | 106 | 124 | 1,133 | 1.49 | 9.1 | 2.9 |
| 1938 | WSH | 33 | 223.1 | 12 | 15 | 1.227 | 3.43 | 221 | 53 | 68 | 3.89 | 0 | 31 | 11 | 85 | 109 | 939 | 1.28 | 8.9 | 2.7 |
| 1936 | BRO | 16 | 32.0 | 0 | 0 | 1.219 | 3.66 | 34 | 5 | 8 | 4.10 | 1 | 0 | 2 | 13 | 18 | 139 | 1.60 | 9.6 | 2.3 |
| 1935 | BRO | 43 | 137.2 | 2 | 9 | 1.315 | 3.92 | 152 | 29 | 41 | 4.28 | 8 | 11 | 11 | 60 | 67 | 579 | 1.41 | 9.9 | 2.7 |
| 1934 | BRO | 44 | 183.2 | 14 | 11 | 1.323 | 3.28 | 210 | 33 | 58 | 4.00 | 5 | 21 | 12 | 67 | 90 | 776 | 1.76 | 10.3 | 2.8 |
| 1933 | BRO | 10 | 40.0 | 2 | 3 | 1.300 | 2.93 | 42 | 10 | 6 | 3.35 | 0 | 3 | 0 | 13 | 17 | 173 | 0.60 | 9.5 | 1.4 |