On April 23rd this season, Clayton Kershaw pitched 6 innings for the win against the Mets. And, on June 14th, Jose Berrios went 7⅔ against the Orioles and also collected the W. What do these two games have in common? Find out after the jump.

Kershaw and Berrios both extended undefeated streaks as a starting pitcher against those two opponents. In both instances, the streaks remain intact since the start of these players’ careers. Kershaw’s win was his 11th in a streak of 17 undefeated starts in his regular season career against the Metropolitans^*, while Berrios notched his 10th W in 13 unblemished career starts against Baltimore. These two streaks (call them “Perfect 10” streaks) are among only 33 since 1901 by pitchers beginning a career with 10 or more wins and nary a defeat, as a starter, against a particular opponent. That number might be even less without expansion, as Kershaw is one of five pitchers with such a streak against the Mets, but the only one of those 5 whose streak did not begin in the Mets’ 40-120 debut season in 1962. Similarly, the only streaks against the Padres (two) and Blue Jays (one) all began in those franchises’ debut seasons, as did one of two streaks against the Senators/Rangers.

*Kershaw has a win and a loss in two post-season starts against the Mets, in the 2015 NLDS.

If you guessed that five such streaks against the Mets is the most for any franchise, you’re right. Here’s that result:

• 5 – Mets
• 3 – Athletics, Browns/Orioles, Mariners
• 2 – Cubs, Senators/Twins, Phillies, Padres, Senators/Rangers
• 1 – Braves, Red Sox, White Sox, Reds, Tigers, Marlins, Pirates, Blue Jays, Expos/Nationals

I won’t keep you in suspense any longer. Here are the Perfect 10 streaks, ordered by number of wins.

Lest there be any confusion, the opponents are denoted by each franchise’s current city, which may be different from where that franchise was located when the streak occurred. Several of these pitchers are (or will be) in the Hall of Fame, and those that aren’t are mostly recognizable names. Indeed, every pitcher on the list, save for Larsen, has a winning record for his career, and every retired pitcher recorded 100+ wins, save for Larsen, Kaufmann and Coveleski (and Coveleski, not to be confused with his younger brother and HoFer Stan, enjoys the distinction of sharing the Tiger franchise record of three consecutive 20 win seasons). Some observations on these streaks:

• Randy Johnson‘s streak against the Cubs, covering 21 seasons, was indeed his entire career. The other streaks (aside from active players) representing an entire career are those by Harry Coveleski against the A’s, Bill Gullickson against the Mariners, and Carl Mays against the Phillies. Mays evidently enjoyed pitching in Philadelphia, as he posted a record unbeaten streak against the Athletics (see below) before switching leagues and going unbeaten against the Phillies.
• The streaks by Johnny Allen, Tony Kaufmann, Pedro Martinez, Jamie Moyer and Derek Lowe were all accomplished with a win in each start of the streak. The surprise among these five is that a majority are from the recent past, when decisions by a starter are no sure thing, as evidenced by a combined 2 CG in 32 streak starts by the last three mentioned. In contrast, Allen and Kaufmann combined for 20 CG in 23 starts in their streaks.
• In addition to the five streaks just mentioned, there are seven others in which the pitcher’s team won every game in the streak, including those in which the pitcher didn’t record a decision. The longest of these 7 streaks is Dizzy Dean‘s 16 gamer, followed by Randy Johnson, Fergie Jenkins and Sandy Koufax, at 14 games.
• Five pitchers recorded streaks with every win coming in a complete game, led by Juan Marichal (17), with Dizzy Dean (12), Lefty Gomez (11), Tony Kaufmann (10) and Johnny Morrison (10) following. Five others had only one CG or none, with all of these streaks coming (unsurprisingly) in the current century.
• All 10 of the starts and wins in Jamie Moyer’s streak came aged 43 or older. Randy Johnson is the only other pitcher with any streak games (two, in Johnson’s case) aged 40 or older. At the other end of the spectrum is Tony Kaufmann, with his entire streak aged 23 or younger, with Gary Bell and Mudcat Grant close behind, aged 24 or younger.
• As would be expected, the ERAs in these streaks are all impressive, with only two above 3.00 and those coming in high-offense eras. Perhaps the best is Pedro Martinez’s 1.26 ERA against the Mariners, coming at the peak of the steroids era and when Seattle was a contending team, led by, for part or all of the streak, such names as Edgar Martinez, Ken Griffey Jr. and Ichiro Suzuki.
• Most, but not all, of these pitchers kept the ball in the yard, with four allowing more than one HR per 9 IP during their streaks, including Jose Berrios (1.39) and Jamie Moyer (1.38) and, more surprisingly, Fergie Jenkins (1.08) and Tom Seaver (1.04). Jenkins and Seaver made up for it by keeping runners off the bases, with 5.33 and 5.67 SO/W ratios, respectively, behind only Marichal’s 6.04 and (in Jenkins’ case) Pedro’s 5.39.

A “perfect 10” streak from the start of career is, of course, just a subset of the same streaks coming at any point in a player’s career, of which there have been 278 since 1901, distributed as shown below:

• 6 – Lefty Grove
• 5 – Walter Johnson
• 4 – Christy Mathewson, Dizzy Dean
• 3 – Cy Young, Joe McGinnity, Mordecai Brown, Ed Reulbach, Jesse Haines, Burleigh Grimes, Freddie Fitzsimmons, Dwight Gooden, Clayton Kershaw
• 2 – 45 pitchers
• 1 – 142 pitchers

Some observations on the perfect 10 streaks leaders:

• Three of Walter Johnson’s five streaks were completely contemporaneous, with the Senators’ ace flummoxing the White Sox, Tigers and Highlanders/Yankees from 1912 to 1914.
• Johnson’s achievement closely followed Christy Mathewson doing the same thing in the NL, besting the Reds, Braves and Superbas/Dodgers from 1908 to 1911. But, it wasn’t just Mathewson. Ed Reulbach’s three streaks came against those same three NL opponents and at much the same time, from 1907 to 1909. And, Mordecai Brown had streaks against two of those three (the Reds and Superbas) again at the same time, from 1906 to 1909 (Cincinnati, Boston and Brooklyn together posted exactly one season higher than 5th place from 1906 to 1911, including a last place finish by the Braves in 4 of those 6 years).
• Only obliquely related to his perfect 10 streaks, but noticed that Joe McGinnity is the only pitcher since 1893 to win 20 games in each of his first 8 seasons. Never posted a losing record, and was more than 100 games over .500 for his career. But my favorite McGinnity stat is this one: he started both ends of a double-header three times in 1903, all in the month of August, posting a 6-0 record with 6 CG in those games, while allowing a total of 10 runs. McGinnity compiled 59 WAR in only 10 seasons (he didn’t play his first major league game until age 28, as he left organized ball for three years after marrying), yet was mentioned on only 1 of 37 ballots cast in his Circle of Greats election. What were we thinking?
• Dean (Reds), Gooden (Cubs), Grimes (Phillies) and Haines (Phillies) are notable as the only pitchers with two separate streaks against the same opponent.
• Cy Young’s three streaks all came, in their entirety, aged 35 and older, the only pitcher with that distinction.
• Freddie Fitzsimmons’ third streak began at age 39, twelve seasons after the start of his second streak; the only larger gap was by Jamie Moyer, with the second of his two streaks beginning at age 43, seventeen years (almost to the day) after the start of his first streak.

The longest unbeaten streaks and most wins and complete games in such streaks are shown below, identifying the pitcher and his streak opponent:

Randy Johnson’s streak span of 21 seasons against the Cubs remains, unsurprisingly, the longest of all 278 streaks, with Clayton Kershaw’s 16 seasons (and counting) against the Mets tied for second with Nolan Ryan‘s mastery of the Pirates from 1971 to 1986 (in half of those seasons Ryan was in the AL, with no opportunity to face the Bucs). Jamie Moyer is next with 15 seasons against the Orioles, followed by Andy Pettitte and Adam Wainwright, each with 14 seasons (and counting for Wainwright), against the Royals and Rockies, respectively. Nine more pitchers have streaks spanning at least 10 seasons.

All 30 franchises have endured at least one such streak, ranging from 25 against the Phillies, to one against the Brewers, Blue Jays and Diamondbacks. The most streaks against an expansion franchise are six, against the Mets and Senators/Rangers. The fewest against an original franchise are five, against the Giants and Yankees. Here’s the full list.

• 25 – Phillies
• 24 – Browns/Orioles
• 23 – Athletics, Braves
• 22 – Reds
• 18 – Pirates
• 17 – Tigers
• 15 – Senators/Twins
• 13 – Cardinals
• 11 – Dodgers
• 10 – Red Sox
• 7 – Cubs, White Sox
• 6 – Mets, Guardians, Senators/Rangers
• 5 – Expos/Nationals, Giants, Mariners, Yankees
• 4 – Angels, Astros, Padres, Royals
• 2 – Marlins, Rays, Rockies
• 1 – Blue Jays, Brewers, Diamondbacks

Those interested can find all 287 perfect 10 streaks here. To close, here are superlatives from these streaks, with currently active streaks denoted by an asterisk. Here are the streaks against AL opponents.

And, for the NL opponents.