William Brennan vs. Mike Marshall — Career Comparison

William Brennan
Baby BoomersFloridaThrows RightBats RightNorth AmericaChicago CubsNational LeagueStarting Pitcher
Mike Marshall
Silent GenerationMichiganThrows RightBats RightNorth AmericaMontreal ExposNational LeagueRelief PitcherCy Young AwardAll-Star

William Brennan built a career as a starting pitcher and Mike Marshall as a reliever — different jobs with different demands — but on the metrics that apply to both, a comparison is still worth making. Mike Marshall posted stronger surface numbers — ERA 3.14 and WHIP 1.332 compared to 5.18 and 1.849 for William Brennan. By the career numbers, Mike Marshall had the better of this cross-role comparison — though era context would sharpen the verdict.

Pitching Stats for William Brennan and Mike Marshall

William Brennan
Career
Per 9 Innings
2
2
Mike Marshall
Careerverified
Per 9 Inningsverified
14
14
William Brennan
Career
Per 9 Innings
12
4.44
Mike Marshall
Careerverified
Per 9 Inningsverified
724
4.7
William Brennan
Career
Per 9 Inningsverified
3
1.11
Mike Marshall
Careerverified
Per 9 Innings
24
0.16
William Brennan
Career
Per 9 Inningsverified
2
0.74
Mike Marshall
Careerverified
Per 9 Innings
97
0.63
William Brennan
Careerverified
Per 9 Innings
2
0.74
Mike Marshall
Career
Per 9 Inningsverified
112
0.73
William Brennan
Careerverified
Per 9 Inningsverified
50
50
Mike Marshall
Career
Per 9 Innings
46.41
46.41
William Brennan
Careerverified
Per 9 Inningsverified
25
25
Mike Marshall
Career
Per 9 Innings
3.31
3.31
William Brennan
Career
Per 9 Innings
0
0
Mike Marshall
Careerverified
Per 9 Inningsverified
3
0.02
William Brennan
Career
Per 9 Innings
0
0
Mike Marshall
Careerverified
Per 9 Inningsverified
1
0.01
William Brennan
Career
Per 9 Innings
0
0
Mike Marshall
Careerverified
Per 9 Inningsverified
188
1.22
William Brennan
Careerverified
Per 9 Innings
14
5.18
Mike Marshall
Career
Per 9 Inningsverified
484
3.14
William Brennan
Career
Per 9 Innings
5.18
5.18
Mike Marshall
Careerverified
Per 9 Inningsverified
3.14
3.14
William Brennan
Career
Per 9 Innings
6.09
6.09
Mike Marshall
Careerverified
Per 9 Inningsverified
3.29
3.29
William Brennan
Career
Per 9 Innings
4.44
4.44
Mike Marshall
Careerverified
Per 9 Inningsverified
3.65
3.65
William Brennan
Career
Per 9 Innings
0.312
0.312
Mike Marshall
Careerverified
Per 9 Inningsverified
0.249
0.249
William Brennan
Career
Per 9 Innings
73
27
Mike Marshall
Careerverified
Per 9 Innings
4160
27
William Brennan
Career
Per 9 Innings
24.1
9
Mike Marshall
Careerverified
Per 9 Innings
1386.2
9
William Brennan
Careerverified
Per 9 Innings
29
10.73
Mike Marshall
Career
Per 9 Inningsverified
1281
8.31
William Brennan
Career
Per 9 Innings
10.73
10.73
Mike Marshall
Careerverified
Per 9 Inningsverified
8.31
8.31
William Brennan
Careerverified
Per 9 Innings
2
0.74
Mike Marshall
Career
Per 9 Inningsverified
79
0.51
William Brennan
Career
Per 9 Innings
0.74
0.74
Mike Marshall
Careerverified
Per 9 Inningsverified
0.51
0.51
William Brennan
Career
Per 9 Innings
0.17
0.17
Mike Marshall
Careerverified
Per 9 Inningsverified
0.11
0.11
William Brennan
Careerverified
Per 9 Innings
14
5.18
Mike Marshall
Career
Per 9 Inningsverified
514
3.34
William Brennan
Careerverified
Per 9 Innings
2
0.74
Mike Marshall
Career
Per 9 Inningsverified
52
0.34
William Brennan
Career
Per 9 Innings
5.18
5.18
Mike Marshall
Careerverified
Per 9 Inningsverified
3.34
3.34
William Brennan
Career
Per 9 Inningsverified
18
6.66
Mike Marshall
Careerverified
Per 9 Innings
880
5.71
William Brennan
Careerverified
Per 9 Inningsverified
6.66
6.66
Mike Marshall
Career
Per 9 Innings
5.71
5.71
William Brennan
Careerverified
Per 9 Inningsverified
1.5
1.5
Mike Marshall
Career
Per 9 Innings
1.22
1.22
William Brennan
Careerverified
Per 9 Inningsverified
1.315
1.315
Mike Marshall
Career
Per 9 Innings
1.005
1.005
William Brennan
Careerverified
Per 9 Innings
2
0.74
Mike Marshall
Career
Per 9 Inningsverified
72
0.47
William Brennan
Careerverified
Per 9 Innings
1
0.37
Mike Marshall
Career
Per 9 Inningsverified
31
0.2
William Brennan
Careerverified
Per 9 Innings
1
0.37
Mike Marshall
Career
Per 9 Inningsverified
7
0.05
William Brennan
Career
Per 9 Inningsverified
109
40.32
Mike Marshall
Careerverified
Per 9 Innings
5842
37.92
William Brennan
Career
Per 9 Innings
2
0.74
Mike Marshall
Careerverified
Per 9 Inningsverified
549
3.56
William Brennan
Careerverified
Per 9 Innings
15
5.55
Mike Marshall
Career
Per 9 Inningsverified
548
3.56
William Brennan
Career
Per 9 Innings
5.55
5.55
Mike Marshall
Careerverified
Per 9 Inningsverified
3.56
3.56
William Brennan
Careerverified
Per 9 Inningsverified
0
0
Mike Marshall
Career
Per 9 Innings
115
0.75
William Brennan
Careerverified
Per 9 Innings
1
0.37
Mike Marshall
Career
Per 9 Inningsverified
37
0.24
William Brennan
Career
Per 9 Inningsverified
3
1.11
Mike Marshall
Careerverified
Per 9 Innings
90
0.58
William Brennan
Career
Per 9 Innings
1.767
1.767
Mike Marshall
Careerverified
Per 9 Inningsverified
1.295
1.295
William Brennan
Career
Per 9 Inningsverified
93
34.4
Mike Marshall
Careerverified
Per 9 Innings
5145
33.39
William Brennan
Career
Per 9 Innings
1.25
1.25
Mike Marshall
Careerverified
Per 9 Inningsverified
0.76
0.76
William Brennan
Career
Per 9 Innings
0.37
0.37
Mike Marshall
Careerverified
Per 9 Inningsverified
0.287
0.287
William Brennan
Careerverified
Per 9 Inningsverified
40.32
40.32
Mike Marshall
Career
Per 9 Innings
37.92
37.92

Fielding Stats for William Brennan and Mike Marshall

William Brennan
Career
Per 9 Innings
2
2
Mike Marshall
Careerverified
Per 9 Inningsverified
14
14
William Brennan
Career
Per 9 Innings
12
4.44
Mike Marshall
Careerverified
Per 9 Inningsverified
724
4.7
William Brennan
Career
Per 9 Inningsverified
3
1.11
Mike Marshall
Careerverified
Per 9 Innings
24
0.16
William Brennan
Career
Per 9 Innings
73
27
Mike Marshall
Careerverified
Per 9 Innings
4159
27
William Brennan
Career
Per 9 Innings
24.1
9
Mike Marshall
Careerverified
Per 9 Innings
1386.1
9
William Brennan
Career
Per 9 Inningsverified
4
1.48
Mike Marshall
Careerverified
Per 9 Innings
105
0.68
William Brennan
Career
Per 9 Innings
4
1.48
Mike Marshall
Careerverified
Per 9 Inningsverified
283
1.84
William Brennan
Careerverified
Per 9 Inningsverified
0
0
Mike Marshall
Career
Per 9 Innings
15
0.1
William Brennan
Career
Per 9 Inningsverified
8
2.96
Mike Marshall
Careerverified
Per 9 Innings
403
2.62
William Brennan
Career
Per 9 Inningsverified
8
2.96
Mike Marshall
Careerverified
Per 9 Innings
388
2.52
William Brennan
Careerverified
Per 9 Inningsverified
100
100
Mike Marshall
Career
Per 9 Innings
96.28
96.28
William Brennan
Careerverified
Per 9 Inningsverified
0.667
0.667
Mike Marshall
Career
Per 9 Innings
0.536
0.536
William Brennan
Careerverified
Per 9 Inningsverified
25
25
Mike Marshall
Career
Per 9 Innings
3.31
3.31
William Brennan
Career
Per 9 Innings
0
0
Mike Marshall
Careerverified
Per 9 Inningsverified
25
0.16
William Brennan
Career
Per 9 Innings
0
0
Mike Marshall
Career
Per 9 Innings
0
0
William Brennan
Career
Per 9 Innings
0
0
Mike Marshall
Career
Per 9 Innings
0
0
William Brennan
Career
Per 9 Innings
0
0
Mike Marshall
Career
Per 9 Innings
0
0
William Brennan
Career
Per 9 Innings
0
0
Mike Marshall
Career
Per 9 Innings
0
0

Hitting Stats for William Brennan and Mike Marshall

William Brennan
Career
Per 600 PA
2
2
Mike Marshall
Careerverified
Per 600 PAverified
14
14
William Brennan
Career
Per 600 PA
12
1440
Mike Marshall
Careerverified
Per 600 PAverified
725
2004.61
William Brennan
Career
Per 600 PA
5
600
Mike Marshall
Careerverified
Per 600 PA
217
600
William Brennan
Career
Per 600 PA
3
360
Mike Marshall
Careerverified
Per 600 PAverified
179
494.93
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
0.196
0.196
William Brennan
Career
Per 600 PA
0.5
0.5
Mike Marshall
Careerverified
Per 600 PAverified
0.558
0.558
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
35
96.77
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
33
91.24
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
1
2.76
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Career
Per 600 PA
0
0
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
1
2.76
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
2
5.53
William Brennan
Career
Per 600 PA
Mike Marshall
Careerverified
Per 600 PAverified
0.057
0.057
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
0.006
0.006
William Brennan
Career
Per 600 PA
Mike Marshall
Careerverified
Per 600 PAverified
0.029
0.029
William Brennan
Career
Per 600 PA
0.04
4.24
Mike Marshall
Careerverified
Per 600 PAverified
10.74
29.7
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
39
107.83
William Brennan
Career
Per 600 PA
1
120
Mike Marshall
Careerverified
Per 600 PAverified
53
146.54
William Brennan
Career
Per 600 PA
0.25
0.25
Mike Marshall
Careerverified
Per 600 PAverified
0.266
0.266
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
0.218
0.218
William Brennan
Career
Per 600 PA
0.25
0.25
Mike Marshall
Careerverified
Per 600 PAverified
0.484
0.484
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
0.022
0.022
William Brennan
Career
Per 600 PA
0.113
0.113
Mike Marshall
Careerverified
Per 600 PAverified
0.174
0.174
William Brennan
Career
Per 600 PA
0.333
0.333
Mike Marshall
Careerverified
Per 600 PAverified
0.39
0.39
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
0.231
0.231
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
11
30.41
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
16
44.24
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
26
71.89
William Brennan
Career
Per 600 PA
0.04
4.34
Mike Marshall
Careerverified
Per 600 PAverified
12.99
35.91
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
1
2.76
William Brennan
Career
Per 600 PAverified
1
120
Mike Marshall
Careerverified
Per 600 PA
17
47
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Career
Per 600 PA
0
0
William Brennan
Careerverified
Per 600 PA
2
240
Mike Marshall
Career
Per 600 PAverified
33
91.24
William Brennan
Career
Per 600 PA
2.5
2.5
Mike Marshall
Careerverified
Per 600 PAverified
6.58
6.58
William Brennan
Career
Per 600 PA
0.5
0.5
Mike Marshall
Careerverified
Per 600 PAverified
0.52
0.52
William Brennan
Career
Per 600 PAverified
1
120
Mike Marshall
Careerverified
Per 600 PA
18
49.77
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Careerverified
Per 600 PAverified
2
5.53
William Brennan
Careerverified
Per 600 PAverified
0
0
Mike Marshall
Career
Per 600 PA
2
5.53
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Career
Per 600 PA
0
0
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Career
Per 600 PA
0
0
William Brennan
Career
Per 600 PA
0
0
Mike Marshall
Career
Per 600 PA
0
0
William Brennan
Career
Per 600 PA
Mike Marshall
Career
Per 600 PA