Pitching in Tom Seaver's shadow for so long, Jerry Koosman is criminally underrated, I think, in terms of his place in Mets history. According to the Ultimate Met Database, Koosman ranks 16 out of 910, in terms of website's search history. That puts him behind less important or impressive Mets, such as Dave Kingman, or Lee Mazzilli. When I was on the train coming home from a game a few weeks ago, a father sitting near me was teaching his son some Mets history, listing some of the franchise's greatest players, and I don't recall him mentioning Koosman. Obviously, though, if we're mulling retiring his number, here, he must've had, at the very least, a decent time with us, right? Let's take a look back at Jerry Koosman's baseball career.
Jerry Koosman was discovered not by scouts, but by the son of a Shea Stadium usher. With the Vietnam War raging, Koosman enlisted in the U.S. Army, like many other young men, as to avoid arbitrarily being drafted and sent to war- volunteering gave you more control over your future. While at Fort Bliss, Texas, Koosman regularly participated in baseball activities. The son of the aforementioned Shea Stadium usher wrote his father about the left-hander's baseball prowess, and, defying conventional wisdom of today, the usher actually was able to influence the Mets' front office to send scouts to see Koosman pitch. So impressed with his performance were they, that they offered him a contract after he was discharged from his military service.
Koosman spent three years in the Minor Leagues. At age 22, he spent most of 1965 with the Greenville Mets of the Western Carolinas League, in Single-A ball. He pitched relatively poorly, ending up with a 4.71 ERA in 107 innings, giving up about 8 hits per nine innings, and walking about five every nine innings. This led the Mets front office to doubt the left-hander's ability to succeed in organized baseball. He would have been cut had it not been for Assistant Minor League director Joe McDonald's intercession. The reason? Koosman had been wired money en route to Spring Training, and owed the team money. They didn't want to release him until they had been paid back, and as a result, retained Koosman for the immediate future, until he could pay the team back. He began 1966 in Auburn, playing for the Auburn Mets of the New York-Penn League, and proved that 1965 was just a blip on the radar. In Auburn, he threw 170 innings with an ERA of 1.38, giving up about six hits per nine innings, and walking about two per nine innings. His 1967 season at Triple-A, with the Jacksonville Suns of the Independent League showed that he was the real deal- in 178 innings, he posted an ERA of 2.43, giving up about seven hits per nine innings, walking about two per nine innings, and striking out about nine per nine innings.
Koosman debuted in the MLB at the end of 1967 for a cup-of-coffee, but played his first full season in 1968. He went 19-12 for the year, throwing 263.2 innings and ending the year with a 2.08 ERA. He threw 17 complete games, and of those 17, 7 were shutouts. He struck out about six batters per nine innings, walked about two per nine innings, and gave up about eight hits per nine innings. His 19 wins, 7 shutouts, and sterling 2.08 ERA set franchise records for the time, breaking records Tom Seaver set just the year before. The two of them leapfrogging over each other in the record books would become a constant theme during their Mets careers. Koosman was also elected to the All-Star Game that year, where he pitched a scoreless ninth innings to get the save and secure the National League's 1-0 victory. He also was thirteenth in National League MVP voting, and second in National League Rookie of the Year voting, narrowly being edge out by Johnny Bench. Koosman's 1968 season was his best in a Met uniform, posting a 6.8 WAR for the season, which would also be his highest single-season WAR accumulation for his career.
1969 (I know, you're not supposed to start sentences with numbers, but I'm not writing 1969 out!) was more of the same for Koosman. He ended the regular season with a 17-9 record, with a 2.28 ERA, in 241 IP, with 16 complete games, and 6 shutouts. He struck out about seven batters per nine innings, walked about three, and gave up about seven hits. He was once again elected to the All-Star Game, and received National League MVP votes. His performance down the stretch, including the postseason, was excellent. Koosman was 8 of his final 9 regular season performances, and while he didn't fare well in the NLCS against the Milwaukee Braves, he was dominant against the powerful Baltimore Orioles. Koosman pitched Games 2 and 5 of the 1969 World Series, winning both, allowing only seven hits and four earned runs in 17.2 innings.
In the early 1970s, Koosman would regress somewhat, throwing fewer innings, giving up more walks, hits, and runs, while striking out fewer batters. Arm problems in 1971 and 1972 are mostly to blame. By 1973, when the Mets made another unexpected playoff run, Koosman was himself again- in 263 innings pitched, he had an ERA of 2.84, though his hits per nine innings stayed elevated, and his strikeouts per nine innings stayed depressed. In the postseason, Koosman was again dominant, allowing two runs in eight innings pitched in the NLCS against the Cincinnati Reds in a complete game victory, and three runs in his two starts against the eventual World Champion Oakland A's.
Koosman would stay relatively dominant for the rest of his Mets career. Throughout the rest of the 1970s, Koosman was an above-average pitcher. In 1976, Koosman pitched 247.1 innings, with a 2.69 ERA, breaking the 20-win plateau for the first time in his career, going 21-10 for the season. He matched his career high of 17 complete games, 3 of which were shutouts. He tied a career low with 2.4 walks per nine innings, and established a then-career high of 7.3 strikeouts per nine innings. Koosman placed second in National League Cy Young voting, being edged out by Randy Jones. Somewhat ironically, after setting a career high in wins in 1976, he lost a career high 20 games in 1977, leading the MLB in losses, showing the volatility of the stat. After another poor season, in terms of wins and losses for both the team and himself, Koosman requested a trade. At the end of the 1978 season, Jerry was traded to the Minnesota Twins for Greg Field and Jesse Orosco. Already in his late 30s, Koosman would have an excellent year in his first year with the Twins, but would otherwise decline, until his retirement in 1985, with the Philadelphia Phillies.
During his twelve-year tenure with the Mets, Koosman went 140-137, with a 3.09 ERA. He started 348 games, and of those 348, 108 were complete games, and 26 were shutouts. Over those 2,544.2 innings pitched for the Mets, his ERA+ was a 113. In the 26.1 innings he pitched for the Mets in the World Series, he had a 2.39 ERA- and, it's not like he pitched against punchless teams. He was a two-time All-Star, appearing in the 1968 and 1969 games, his only two All-Star Game appearances. During his Mets years, he accrued a 41.8 WAR, which averages out 3.5 WAR per year during that time. In 1989, he was inducted into the Mets Hall-of-Fame.
Thus far, Tom Seaver, is the only Met who has had his number retired, and is also the only Met player in the Baseball Hall-of-Fame as a Met. So, there definitely seems to be a correlation between retired numbers and the Hall-of-Fame, at least for our team. Is Jerry Koosman a borderline Hall-of-Famer, who never made it to Cooperstown, but should have? According to Baseball-Reference's Hall of Fame statistics, Koosman comes short being afforded a place in Cooperstown. According to the Gray Ink Test, he is worth 130 points, when the average Hall-of-Famer is worth 185. Looking at the Hall of Fame Monitor for pitching, Koosman places in at 59, while the likely Hall-of-Famer is 100. Looking at the Hall of Fame Standards for pitching, Koosman places in at 33, while the average Hall-of-Famer is 50. So, Koosman isn't a Hall-of-Famer who just was never voted in despite deserving the honor. In reality, he occupies a tier below "Borderline Hall-of-Famer".
Despite that, I believe Jerry Koosman should be honored by having his number ‘36' retired in perpetuity for the Mets. Koosman was an important part of the 1969 Mets, and has a World Series ring to show for it. Along with Tom Seaver, Koosman was part of one of the more formidable lefty-righty pitching duos in the National League during the late 1960s and early 1970s, and helped anchor an above-average pitching rotation during that time (often referred to as the ‘Tom and Jerry Show'). Koosman ranks among the longest tenured Mets, accumulated 41.8 WAR with the team, and is among the best lefthanders to have ever played with the Mets. He still holds, or is near the top, of many team records, such as games started, innings pitched, wins (and losses!), complete games, shutouts, ERA, strikeouts, among others.