The numbers behind O's historic streak

This story was excerpted from Jake Rill’s Orioles Beat newsletter. To read the full newsletter, click here. And subscribe to get it regularly in your inbox.

Baseball is a sport filled with streaks -- winning streaks, losing streaks, hitting streaks, games played streaks and others.

For more than two years, the most noteworthy streak for the Orioles was a sweepless streak.

From May 13-15, 2022, Baltimore got swept during a three-game series at Detroit. The O’s losing streak then continued back home at Camden Yards, reaching six after dropping the first three contests in a four-game set vs. the Yankees. But the Orioles prevented a sweep with a 9-6 win in the finale on May 19, 2022.

It wasn’t known at the time, but that one victory was the start of an historic run. It marked the first of 106 consecutive multi-game regular-season series in which Baltimore was not swept, a streak that didn’t end until earlier this week, when the O’s lost all three of their games at St. Louis from Monday-Wednesday.

“It’s been a lot of fun to go that many series without having that feeling, losing all the games in a series,” said outfielder Austin Hays, who was with the Orioles for the entirety of the streak. “Doesn’t happen very often.”

That’s for sure. Here’s context for where Baltimore’s sweepless streak ranks in AL/NL history:

Longest regular-season sweepless streaks (min. two decisions, per Elias Sports Bureau)
1. 1942-44 Cardinals: 124
2. 1906-09 Cubs: 115
3. 2022-2024 Orioles: 106

Longest regular-season sweepless streaks (min. two games, per Elias Sports Bureau)
1. 1942-44 Cardinals: 125
T-2. 1903-05 Giants: 106
T-2. 2022-2024 Orioles: 106

The previous existence of ties is the reason for the differences between the older teams on those lists. For example, the Cubs played a two-game set as a doubleheader vs. the Brooklyn Dodgers on Sept. 29, 1907 -- a 5-2 loss and a 2-2 tie. There were two games, but there weren’t two decisions, hence their inclusion on the former list and their exclusion from the latter.

The distinction of “regular season” is also important. When the Orioles’ streak was at 91, they got swept by the Rangers in the 2023 American League Division Series, losing all three games.

However, much like how postseason stats don’t factor into a player’s all-time numbers -- Cal Ripken Jr.’s AL/NL record games played streak is 2,632, which doesn’t include the 28 postseason contests he played in from 1982-98 -- Baltimore’s sweepless streak carried on into the start of 2024.

What were the odds of the Orioles going 106 straight multi-game regular-season series without getting swept? MLB.com senior data architect Tom Tango calculated the answer.

Baltimore went 199-134 during its sweepless streak. It played series that consisted of five games (one), four (19), three (77) and two (nine).

Based on the Orioles’ .598 winning percentage over that span, as well as how many series of each length they played, their chances of avoiding a sweep in all 106 series based on a random distribution of wins and losses would be only 0.07%.

So the O’s defied those low odds by continuing to extend their sweepless streak, which they did 14 times with their backs against the wall in the finale of a series -- including on May 8 at Washington (a 7-6 win in 12 innings) and on May 15 vs. Toronto (a 3-2 victory featuring an Adley Rutschman walk-off two-run homer in the bottom of the ninth inning).

Baltimore’s remarkable streak ended with a three-game series loss to the Cardinals in which the Orioles tallied only eight runs on 14 hits in a rain-soaked week at Busch Stadium.

“We wanted to keep the streak alive, of course,” manager Brandon Hyde said.

That may not have happened, but Hays made a vow on behalf of the Orioles.

“Now, we’ll start a new streak next series,” Hays said.

Sure enough, the O’s won their first two games vs. the White Sox in Chicago on Thursday and Friday. The new streak is at one, and knowing this team -- which hasn’t lost more than three consecutive games this year and hasn’t had a losing streak longer than four since its six-game skid just before its sweepless run -- it could be another long one.