The Greatest Scoreless Innings Streak Ever
By Sky Andrecheck

On Tuesday, I posted about Zack Greinke's 38-inning scoreless streak and showed how it was the equal of the famous Don Drysdale streak in 1968. Due to the context of the times and the quality of the opponents, Greinke's 38-inning streak was actually just as difficult as Drysdale's 58-inning streak. But of course Drysdale and Greinke are not the only pitchers to ever compile long streaks. This article follows up on the last one, and tries to determine the most impressive scoreless inning streak of all-time.

The record holder of course, is Orel Hershiser, who pitched in 59 consecutive scoreless innings, dramatically pitching 10 innings in the final game of the season to overtake Drysdale. Other contenders for the title of toughest scoreless inning streak are Walter Johnson, in the American League, who pitched 55 2/3 scoreless innings in 1913 for Washington, and Sal Maglie's 45-inning streak in a tough pitchers' environment in 1950 for the New York Giants. There are other notable streaks, such as Bob Gibson's 47-inning streak in 1968 and Jack Coombs' 53-inning streak in 1910, but because they were accomplished in even stronger pitchers' environments than Hershiser's, we can see right away that they won't be tougher than his record-holding streak.

Looking back at all three of the streaks, we can determine about how likely it was that a quality pitcher could complete each streak. The streak with the lowest probability of course was the toughest.

Using the same methodology from Tuesday's article, I calculated the expected runs allowed for each game of the streak, based on the opponent, the park, and whether the pitcher was playing at home. I then made a small adjustment for defense to account for poor defenses having a higher probability of giving up unearned runs (which would end the streak).

Let's first take a look at Hershiser's streak. Performed in 1988, it was a pitchers' environment. Dodger Stadium was significantly less pitcher friendly than during Drysdale's streak, but was still a pitchers' park. However, only 18 of his innings were at home, making the streak even more impressive. The following chart shows the seven games that composed his streak.


Based on opponent, park, and home field, the average expected runs per 9 IP during the streak was 3.74. Cutting this number down by 25% to get the expected number of runs given up by a good pitcher, not simply an average one, we get 2.99 expected runs per 9 IP. This translates roughly into a probability of throwing a scoreless inning at .801, which he accomplished 59 straight times - very impressive. The probability of completing the streak was .801 ^ 59 = 1 in 485,000. With those odds, the Bulldog certainly pulled off an incredible feat. This was about 5 times tougher than Greinke or Drysdale's feat, but was it the best ever?

Next let's look at the dark horse of the group, Sal Maglie. Being a younger fan, I had not heard of Maglie's scoreless inning streak until recently, and it certainly doesn't have the cache of Drysdale's or Hershiser's. But was it as good or better? Maglie started his streak on August 16th against Brooklyn and ended it September 13th against Pittsburgh, throwing four shutouts in between. 1950 was certainly a hitters year, which made the streak all the more impressive. Below is a chart of the opponents and the expected runs given up by an average pitcher in each of the games.


Maglie's opponents varied between the tough Brooklyn Dodgers and the lowly Pirates, but on average, the average pitcher would be expected to give up 4.81 runs per 9 IP during the streak. For a "good" pitcher, we reduce this to 3.85. Translating this to the probability of throwing a scoreless inning, we get approximately .750. Therefore, the probability of completing the streak was approximately .750 ^ 45 = 1 in 419,000. The Barber's feat was nearly as good as Hershiser's! While he wasn't quite as good the numbers are extremely close, especially considering that there is some estimation error. Still, it's surprising that the unknown Maglie streak is nearly the equal of Hershiser's celebrated feat. The context means that much. But could anyone best both Maglie and Hershiser?

Now let's turn our eyes to Walter Johnson's feat. In 1913 he broke Jack Coombs' record in a tougher pitching environment by throwing 55 2/3 scoreless innings. He started the streak after giving up a run in the first inning of opening day, and didn't allow another one until May 14! Pitching in a combination of starts and relief, he was dominant in his first nine outings. I was able to cobble together the games of his streak (partly due to this nice blog on the Senators and Twins) except for one two inning April relief appearance against whom I could not determine. Below is a chart showing his opponents and the average expected runs per 9 IP.


The average runs per 9 IP was 3.91 for an average pitcher and for a good pitcher this number is reduced to 3.13. Converting this to a probability of a scoreless inning we get about .792. Therefore, over 55.2 innings pitched, the probabilty of a good pitcher completing his streak was .792 ^ 55.67 = 1 in 435,000. This makes Johnson's streak not quite as impressive as Hershiser's, but very close. Due to potential errors in the conversion of runs per nine innings to probability, I think a case could be made for either Maglie, Hershiser, or Johnson to have had the toughest streak, as all three are very close. The difference between them is only one or two innings on a level playing field, so had any of them continued their streak for just a little longer, they would have had clearly the toughest streak of the three.

Can the trio's "record" for most impressive streak be broken? In today's environment, a pitcher (such as Greinke, who now has another 13-inning streak going), would need to reach about 44 innings to match Maglie, and 45 innings to surpass all three streaks. Of course, the fanfare won't start until he reaches 60, but he'll have beaten the toughest streak ever long before that.


By this calculation, does someone need to hit more than 56 games to beat DiMaggio since pitching was relatively tougher in the 50's?

I'm a Dodger fan that drove down to San Diego to see Orel break that record at the Murph. We knew he needed to go 10 to break the record, but the dodger offense was so attriciousthat year it seemed possible, if not probable. He was utterly untouchable then, right through the post season. It was a really fun thing to watch.

Actually it's about as easy to hit now as in 1941, so the streak would have about the same difficulty. If Rose had done it in 1978 (when hitting was harder), it would have been a more difficult feat than Joe D's. Of course, the hitting streak has other factors too, principally the batting order.

A good follow-up article to the Drysdale-Greinke comparison.

One minor nit-pick: In discussing Hershiser, you have R/G in the table and then seemingly interchange R/9IP as the equivalent label. They are not, thanks to games that require extra innings. For example, B-Ref has the 1988 Expos at an average of 3.8 R/9IP. You can find that here (you'll have to copy/paste, I couldn't get the link to work):

As I type this, I'm beginning to wonder if your numbers are a little off. Compare your numbers in the Hershiser table to this:

Now that Zach's given up a couple, maybe we should search for the greatest margin of improbability. Say best rate over 100 innings?

You are right that where the table says R/G, it really means runs per 9 IP. The discrepancy you mention is the fact that the numbers in the chart are adjusted for park. The "Total" row also factors in defense and whether the pitcher was pitching at home. I probably should have done this for the individual rows as well....the chart may not be the clearest ever, but the numbers are right.

Great article Sky. I would be interested to hear how you converted runs per 9 inning to probability of a scoreless inning, if you get the chance.

Thanks for the clarification Sky! That makes sense.

Love the pitching comps. To build on Matt's idea above, about comps through 100IP, here's how Gibson did during his peak run during that 1968 season.

On June 6th, Gibson took the mound at Houston sporting a 4-5 record despite a 1.66 ERA. Nearly 2 months later, Gibson lost in extra innings, throwing 11 IP in defeat. Prior to that start on August 4, Gibson ran his record 10 15-5 and dropped the ERA down to 0.96. After that game on August 4th, Gibson's ERA bloated to 1.08. His very next start was another shutout, dropping the ERA to 1.04.

Starting on June 6, to his last start before August 4, Gibson made 11 starts, completed all 11, so he threw 99IP. In that 99IP, he allowed a total of 3 runs, all of which were earned.

That's 3 total runs in 99IP! Gibby's ERA was less than .3 for that run of nearly 100IP. I don't know if that was the best run, but it has to be up there.

Great question Dave. This is the part of the analysis which could use most improvement. As I explained in the Drysdale/Greinke article, I found yearly empirical data on this from web and matched the scoreless inning % to the proper ERA.

This was pretty easy to do for Greinke and Maglie, but for the others the expected ERA was less than an actual league ERA that had ever been recorded. For this, I extrapolated the data as best I could based on the existing data. A possible improvement might be to build a theoretical model to get a more accurate number.

the average expected runs per 9 IP during the streak was 3.74. Cutting this number down by 25% to get the expected number of runs given up by a good pitcher, not simply an average one, we get 2.99 expected runs per 9 IP.

Uh, isn't this a 20% cut?

As for scoreless streaks, an unusual one that remains a personal favourite occurred in 1966 when over the course of the season Larry Jaster of the Cardinals threw 5 consecutive shutouts against the same club, the pennant winning Dodgers. Jaster, a 22-year-old rookie southpaw, finished the season with exactly 5 shutouts, which was enough to co-lead the NL. He finished his career with just 7 shutouts.

Jaster was the first pitcher since Grover Cleveland Alexander to shut out the same opponent 5 times in one season, although even the great Alex had other starts against the Reds in 1916 so did not record a continuous streak.

Jaster's mastery of the league champs that magical season remains one of the more remarkable if obscure feats that I have witnessed in nearly half a century of following the game.

Good point Bruce - I was a little sloppy with my language. What I did was assume an ERA-plus of 125 - the definition being LeagueERA/PlayerERA. 3.74/2.99=1.25. But working backwards, as you mention, it's actually 20% off the original ERA.


Thanks for the explanation. Very cool way of doing it.