The initial transaction for Milwaukee Brewers general manager David Stearns came just a few weeks after he was on the job when he claimed pitcher Junior Guerra off waivers from the Chicago White Sox.

Not a bad first impression.

Guerra, who began the season at Triple-A Colorado Springs, has been one of the pleasant surprises on the Brewers and perhaps the team's most consistent starting pitcher. After Monday's 1-0 win over Washington and Max Scherezer, in which Guerra tossed 7 1/3 shutout innings, he is 6-1 with a 2.93 ERA, 1.017 WHIP and 7.9 strikeouts per nine innings. Not too shabby for a guy who had pitched in just four major-league innings prior to the 2016 season (and had allowed three runs on seven hits).

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In each of his first two starts with Milwaukee, Guerra allowed four runs in six innings. Since then, he has made 10 starts and allowed more than four earned runs just once (5 in 5 1/3 innings against the Dodgers on June 16) and has a 2.37 ERA and .190 opponent batting average during that span.

And did we mention that Guerra is 31 years old?

Turns out, Guerra is having one of the best rookie seasons by a starting pitcher who is at least 31 years old . . . well, ever.

Yes, it is hard to compare eras with pitchers. There's the Deadball Era, pre-integration, expansion, the Year of the Pitcher in 1968, steroid era and so on. A 3.50 ERA is not equal throughout the years.

One of the best ways to compare, however, is using ERA+, which compares a pitcher's ERA to the league average while adjusting to the pitcher's ballpark. An ERA+ of 100 is right at the average for that season while a lower number is worse and the higher the better.

Since 1901 there have been 54 pitchers who were age 31 or older who made at least 12 starts in a season. Of those 54, only 11 have occurred since 1996 and the majority of those have been pitchers moving over from a Japanese league to the major leagues. Nine made their debut during World War II (1942-45) while 11 began their careers in the Deadball Era (pre-1920).

Among this criteria - pitchers who debuted at 31 or older and started 12 or more games - Junior Guerra is currently second all-time in ERA+.

PITCHER AGE SEASON TEAM G-GS IP H BB K ERA ERA+
Jim Turner 33 1937 BOS (NL) 33-30 256.2 228 52 69 2.38 149
Junior Guerra 31 2016 MIL 12-12 76.2 55 23 67 2.93 143
Orlando Hernandez 32 1998 NYY 21-21 141 113 52 131 3.13 142
Hank Gornicki 31 1942 PIT 25-14 112 89 40 48 2.89 132
George McConnell 34 1912 NYY 23-20 176.2 172 52 48 2.57 131
Hisaschi Iwakuma 31 2012 SEA 30-16 125.1 117 43 101 3.16 121
Bob Logan 35 1945 BOS (NL) 34-25 187 213 53 53 3.18 121
Ray Kremer 31 1924 PIT 41-30 259.1 262 51 64 3.19 120
Hal Haid 31 1929 STL 38-14 154.2 171 66 41 4.07 117
Tsuyoshi Wada 33 2014 CHC 13-13 69.1 67 19 57 3.25 117
Hal Smith 31 1933 PIT 28-19 145 149 31 40 2.86 116
Roger Wolff 31 1942 PHI (AL) 32-25 214.1 206 69 94 3.32 115
Koji Uehara 34 2009 BAL 12-12 66.2 71 12 48 4.05 113
Ed Holley 32 1932 PHI 34-30 228 247 55 87 3.95 112
Hiroki Kurdoa 33 2008 LAD 31-31 183.1 181 42 116 3.73 112
Tot Pressnell 31 1938 BRO 43-19 192 209 56 57 3.56 111
Dazzy Vance 31 1922 BRO 36-31 245.2 259 94 134 3.70 111
Art Fowler 31 1954 CIN 40-29 227.2 256 85 93 3.83 110
Grady Adkins 31 1928 CWS 36-27 224.2 235 89 54 3.73 109
Tommy de la Cruz 32 1944 CIN 34-20 191.1 170 45 65 3.25 108
Hisanori Takahashi 35 2010 NYM 53-12 122 116 43 114 3.61 108
Peaches Davis 31 1936 CIN 26-15 125.2 139 36 32 4.39 107
Masato Yoshii 33 1998 NYM 29-29 171.2 166 53 117 3.93 107
Heinie Meine 33 1929 PIT 22-13 108 120 34 19 4.50 107
Kenshin Kawakami 34 2009 ATL 32-25 156.1 153 57 105 3.86 107
Pete Walker 33 2002 NYM/TOR 38-20 140.1 145 51 80 4.36 106
George Bell 32 1907 BRO 35-27 263.2 222 77 88 2.25 104
Johnny Niggeling 36 1940 STL (AL) 28-20 153.2 148 69 82 4.45 104
Sig Jakucki 34 1944 STL (AL) 35-24 198 211 53 67 3.55 103
Johnny Couch 31 1922 CIN 43-33 264 301 56 45 3.89 102
Dick Newsome 31 1941 BOS 36-29 213.2 235 79 58 4.13 101
Art Delaney 31 1928 BOS (NL) 39-22 191.1 197 56 45 3.78 101
Jocko Thompson 34 1951 PHI 29-14 119.1 102 59 60 3.85 100
Connie Marrero 39 1950 WAS 27-19 152 159 55 63 4.50 100
Oscar Judd 34 1942 BOS 31-19 150.1 135 90 70 3.89 96
Lou Tost 31 1942 BOS (NL) 35-22 147.2 146 52 43 3.53 94
Rip Sewell 32 1939 PIT 52-12 176.1 177 73 69 4.08 94
Steve Gerkin 32 1942 PHI (AL) 21-12 102 112 27 25 3.62 93
Walt Dickson 33 1912 BOS (NL) 36-20 189 233 61 47 3.86 92
Al Papai 32 1949 STL (AL) 42-15 142.1 175 81 31 5.06 90
Dennis Springer 31 1996 CAL 20-15 94.2 91 43 64 4.53 89
Billy Campbell 34 1908 CIN 35-24 221.1 203 44 73 2.60 89
Bill Beckmann 31 1939 PHI (AL) 27-19 155.1 198 41 20 5.39 87
John Martina 34 1924 WAS 24-14 125.1 129 56 57 4.67 87
Stoney McGlynn 35 1907 STL 45-39 352.1 329 112 109 2.91 86
Bob Spade 31 1908 CIN 35-28 249.1 230 85 74 2.74 84
Ed Donnelly 32 1912 BOS (NL) 37-18 184.1 225 72 67 4.35 82
Hap Collard 31 1930 PHI 30-15 127 188 39 25 6.80 81
Orie Arntzen 33 1943 PHI (AL) 32-20 164.1 172 69 66 4.22 81
John Eubank 33 1906 DET 24-12 135 147 35 38 3.53 78
John McPherson 35 1904 PHI 15-12 128 130 46 32 3.66 74
Bill Posedel 31 1938 BRO 33-17 140 178 46 49 5.66 70
Jack McFetridge 33 1903 PHI 14-13 103 120 49 31 4.89 64
Frank Oberlin 31 1907 BOS/WAS 23-12 94.2 105 47 36 4.47 56


Dave Heller is the author of the upcoming book Ken Williams: A Slugger in Ruth's Shadow as well as Facing Ted Williams Players from the Golden Age of Baseball Recall the Greatest Hitter Who Ever Lived and As Good As It Got: The 1944 St. Louis Browns