The Astros acquired right-hander Ryan Pressly from the Twins on July 27, 2018, looking to bolster their bullpen for the stretch run. In his Houston debut, Pressly allowed a home run to the very first batter he faced, Texas’ Rougned Odor.

It’s fair to say that did not set the tone for Pressly’s Astros career.

About two weeks later, on Aug. 10, Pressly allowed his second run in his new uniform. He hadn’t allowed one since -- until Friday night.

A streak that began last Aug. 15 against the Rockies reached 39 games on May 17 when Pressly tossed a clean inning in Boston. That set a new all-time Major League record, passing the mark established by current free agent Craig Kimbrel, for the Braves, between June 14 and Sept. 8, 2011. Pressly then extended his streak to 40 games Monday with a perfect eighth inning against the White Sox.

It finally came to an end Friday, when Pressly entered to begin the eighth inning against the Red Sox at Minute Maid Park and immediately allowed a solo home run to Jackie Bradley Jr.. Pressly went on to allow two more baserunners but got out of the inning without further damage, and Houston still holding a 4-2 lead.

Scoreless streaks of this length are certainly a creation of modern baseball and its specialized bullpen usage. When a reliever works an inning or so at a time, it’s far easier -- but still impressive -- to string together a bunch of zeros. So it’s no surprise that of the 23 streaks of 30-plus games (as of Pressly setting the record), all have taken place since 1997.

It’s also true that these streaks only count runs charged to that pitcher. So if a reliever inherits a baserunner and allows him to score, that doesn’t stop the streak, even if it means the pitcher didn’t quite do his job.

With that in mind, here is a look at the longest streaks of scoreless games in MLB history.

1) Ryan Pressly (HOU), 40 G, 2018-19: Pressly was already having a good year with the Twins before his trade to the Astros in ‘18, but he has reached another level in Houston -- a familiar story for pitchers in recent years. With a high-velocity, high-spin fastball and two dominant breaking pitches (a curveball and slider), Pressly racked up a jaw-dropping 48-to-3 strikeout-to-walk ratio over those 40 games.

2) Craig Kimbrel (ATL), 38 G, 2011: The flame-throwing righty made an electrifying 21-game debut in 2010. He took over as the Braves’ closer the next year, striking out 127 batters in 77 innings, including 67 in 37 2/3 innings during the streak. Kimbrel also converted 25 straight save chances in that time before allowing two runs and blowing an opportunity on Sept. 9 at St. Louis.

3-T) Adam Ottavino (COL), 37 G, 2014-16: Unfortunately for Ottavino, this streak was interrupted by Tommy John surgery in May 2015, which wiped out the rest of his season. Yet he returned to Colorado without any signs of rust the following July, reeling off the final 21 consecutive games until allowing a run on Aug. 27 at Washington.

3-T) Mike Myers (MIL/COL), 37 G, 1999-2000: And here we have an ultimate LOOGY situation. Myers, a southpaw, made 883 relief appearances for nine teams over 13 seasons from 1995-2007, yet pitched only 541 2/3 innings. He frequently faced one batter, with an average of two per appearance during the streak. Myers was traded from Milwaukee to Colorado at the end of 1999 and took his streak through the end of June 2000.

5) J.C. Romero (PHI), 35 G, 2007-08: Also a lefty, Romero was a bit less of a specialist, throwing 28 1/3 innings. He managed to escape unscathed despite 23 walks, not allowing a run for his final 20 games of ‘07 and his first 15 of ‘08, through May 1. Romero ultimately was a key piece on a championship Phillies team, throwing 7 1/3 scoreless frames over eight postseason appearances in 2008, including four in the World Series.

6-T) Wade Davis (KC), 33 G, 2014: It was in ‘14 that Davis went from disappointing one-time starting pitching prospect to lights-out reliever. The Royals shifted him full-time to the bullpen that year, and he responded with a 1.00 ERA and 109 strikeouts in 72 innings, followed by more dominant pitching in the postseason. Davis’ streak ran from June 27 to Sept. 15, during which opponents hit .156/.200/.174 against him.

6-T) Arthur Rhodes (CIN), 33 G, 2010: Rhodes is one of 26 pitchers all-time to appear in 900 career games, and one of just six lefties. This was the penultimate of his 20 MLB seasons, and the only one in which he was made an All-Star, posting a 2.29 ERA at age 40. Rhodes allowed a run in his second game and then not again until June 29, while throwing 30 innings.

6-T) Scott Eyre (CHC), 33 G, 2007-08: It’s not as if Eyre was fantastic in these two seasons, posting an ERA over 4.00 in both. But the lefty finished 2007 with 19 straight scoreless outings and started ‘08 with another 14, through June 13. Unfortunately for Eyre, an injury sidelined him soon after, and upon his return, he was quickly traded to the Phillies in early August.

6-T) Mark Guthrie (NYM), 33 G, 2002: The Mets acquired the 36-year-old lefty from Oakland in the offseason, and he produced a 2.44 ERA across 68 appearances. Guthrie didn’t allow a run from May 25 to Aug. 3, striking out 26 in 27 innings.

10-T) Rex Brothers (COL), 32 G, 2013: This was a career year for the hard-throwing lefty, who had a 1.74 ERA in 72 games, while striking out 10.2 per nine innings. Brothers could be wild -- he walked 16 batters during the streak from April 10 to June 27 -- but opponents slugged under .200 against him in that time.

10-T) J.C. Romero (MIN), 32 G, 2004: Here he is again. Romero did some work as a starter early in his career with little success, but the Twins made him a reliever in ‘02. That work suited him much better, and from June 26 to Sept. 11, 2004, he reeled off 36 scoreless innings while striking out 34 for a first-place club.