In the seventh inning of Sunday afternoon’s game in Houston, Bryce Miller left a sweeper over the inner third of the plate, and Jon Singleton didn’t miss it, hammering a towering two-run shot to right field that yielded a bat flip and gave the Astros a 4-3 lead. With that, the Mariners were stopped short of tying a major league record — a semi-obscure one, but an impressive one nonetheless: the most consecutive games with a starting pitcher allowing no more than two earned runs. The Mariners did rally to win 5-4, sending them to their sixth straight series victory and lifting their record to 19-15, enough to help them preserve their half-game lead over the Rangers (19-16) in the AL West.

The starters’ streak began back on April 10, when Logan Gilbert held the Blue Jays to one run in 7.2 innings, and extended to 21 games through Saturday. Most of the starts were exceptional, and for the stretch, the unit pitched to a 1.38 ERA and a 2.91 FIP, but two of those starts depended upon the earned/unearned run distinction to extend the streak, and two were short outings of four or fewer innings; one of those starts, Emerson Hancock’s clunker last Wednesday against the Braves, was both. Still, even including unearned runs, their 1.86 runs allowed per nine allowed during the streak is impressive.

In the fourth inning of Hancock’s outing against Atlanta, Orlando Arcia’s fly ball clanked off the heel of right fielder Mitch Haniger’s glove for a two-base error; it would have been the second out of the inning. With two outs, the Braves strung together four straight hits and scored four times, with all of the runs unearned, and with Hancock heading for an early exit. The Mariners lost that one, 5-2.

With the 21 consecutive starts of two or fewer earned runs, the Mariners tied the 1917 White Sox — who would go on to win the World Series — for the second-longest such streak since earned runs became an official stat in 1913, according to Elias Sports. Had manager Scott Servais pulled Miller after he’d thrown six innings of four-hit ball and allowed two runs, the Mariners would have tied the 1915 Senators for the record at 22 games. Hindsight is 20-20, but it’s tough to blame Servais for sticking with Miller, who’d thrown just 77 pitches when the inning began and had already worked through the top four hitters of the Astros’ lineup for a third time. That said, in the sixth inning, he’d allowed a single to Jose Altuve and a two-run homer to Kyle Tucker.

The 25-year-old Miller was not quite as sharp as in his previous turn against the Braves in Seattle last Monday, when he and opposing pitcher Max Fried each strung together six hitless innings, something that had happened just one other time since the start of 2015; on April 3, 2021, the Brewers’ Corbin Burnes and the Twins’ José Berríos both took no-hitters through six, though neither one finished the job. In fact, to find the only time in the past half-century that one pitcher hung on to complete a no-hitter while the other one’s bid lasted at least six innings, you’d have to go back to June 10, 1997, when the Marlins right-hander Kevin Brown went the distance and Giants righty William Van Landingham spun 6.1 no-hit innings.

Anyway, in last Monday’s game, Ronald Acuña Jr. ended Miller’s bid for a no-hitter with an infield single to lead off the seventh, and he quickly stole both second and third, then scored on an Ozzie Albies sacrifice fly for the game’s first run. Meanwhile, Fried got the hook after six and reliever Pierce Johnson struck out the side in the seventh. But in the eighth Josh Rojas singled off Joe Jiménez; the Mariners eventually won 2-1 on Mitch Garver’s walk-off two-run homer in the ninth.

The Mariners were just 4-8 when they began their streak, but have gone 15-7 since. Their rotation now owns the majors’ second-lowest ERA (2.98) and third-lowest FIP (3.47), trailing only the Red Sox (2.63) in the former category and Boston and the Phillies (3.33 and 3.41, respectively) in the latter. Gilbert ranks fourth in the AL with a 1.69 ERA, while Miller is 11th at 2.61; meanwhile, Kirby is third in FIP at 2.09, with Castillo 10th at 2.94 and Gilbert 13th at 3.24. Kirby is fourth in the league with 1.4 WAR, Castillo ninth at 1.1, and Gilbert 12th at 0.9. Castillo (28.7%), Gilbert (28.2%), Miller (26.6%), and Kirby (26.3%) all rank among the league’s top 15 in strikeout rate as well. The Mariners’ bullpen has also pitched effectively, with the majors’ third-lowest ERA (2.72) and ninth-lowest FIP (3.54).

For as dominant as Seattle’s pitchers have been, it’s fair to suggest that some of their run prevention is owed to their surroundings. The Mariners have scored just 3.61 runs per game (12th in the AL) while allowing a major league low 3.24. At T-Mobile Park, the team and its opponents are averaging just 3.07 runs per game while combining to hit an unsightly .198/.265/.327 with a .258 BABIP (29 points below the major league average) and a 73 wRC+. The Mariners themselves are hitting .223/.302/.366 (98 wRC+) overall. Check out these splits:

The Mariners aren’t a bad team offensively if you take them out of T-Mobile, but at home it’s always the Year of the Pitcher. It’s no state secret that T-Mobile tends to lag in most systems’ park factors, including ours and those of Statcast. One major reason for this is the marine layer, “a shallow layer of air that forms when warm air moves atop a body of cooler water and becomes saturated with water vapor,” as Adam Jude of the Seattle Times explained in a recent feature. With the Mariners’ average game time temperatures of just 53.3 degrees (third-coldest in the majors behind Pittsburgh’s PNC Park and Chicago’s Wrigley Field), that cold air means more drag, which shortens the flight distances of baseballs. A 2017 study by David Kagan and Chris Mitchell for The Hardball Times Annual estimated that the effect amounted to a six-foot reduction of fly ball distances at the majors’ six West Coast venues. Here’s a comparison between fly balls at T-Mobile for 2023 and ’24 and those at the other MLB ballparks, excluding Coors Field, where the ball of course carries further:

Whoa. Last year, fly balls at T-Mobile averaged 11 feet less than those at other venues besides Coors; the batting average on those balls was 14 points lower than the rest of the majors, the slugging percentage 65 points lower, the wOBA 28 points lower. This year, though fly balls are averaging just 7 feet less in distance, the gap in offensive production is even wider: 47 points of batting average, 69 points of slugging percentage, and 44 points of wOBA. Note that all of this is happening with the roof closed for 31% of the games at T-Mobile this year (six of 19) — in theory, producing more hitter-friendly conditions — compared to 21% for all of last year (17 of 81).

Setting the marine layer aside, it’s worth noting that T-Mobile is a difficult place to hit for other reasons. It has more foul territory than the average park, for one thing, and it also produces a strikeout rate that’s well above the major league-wide rate. Whether it comes from the psychology of hitting at T-Mobile given the marine layer (or other factors) or it’s a product of the batter’s sight lines, it’s a consistent effect, with Statcast’s rolling three-year park factors among the highest in the majors. Currently, T-Mobile is at 112 (first among the 30 teams); last year, the factor was 110 (second), and the year before that it was 107 (fourth). Overall, batters struck out 22.7% of the time last season, but they did so 26.2% of the time at T-Mobile and 21.9% at all other venues (this time including Coors), for a gap of 4.3%. This year, they’re doing so 22.5% of the time overall, with a 28.9% rate at T-Mobile and 21.5% at all other venues, for a gap of 7.4%.

This is all happening despite the Mariners’ stated focus on cutting down on strikeouts by shedding the likes of Eugenio Suárez, Jarred Kelenic, and Teoscar Hernández — all of whom had strikeout rates of 30% or higher — this past offseason. Hernández, who spent just one year in Seattle after being traded by the Blue Jays, is thriving with the Dodgers despite striking out more often (31.8% vs. 31.1%); in the spring he told reporters that he had trouble picking up pitches at T-Mobile. “For some reason, I always see the pitcher like sideways, not straight,” he said. “I couldn’t figure it out, how to be in a straight position with the pitcher. That was hard for me.”

In a recent investigation at Baseball Prospectus, Patrick Dubuque noted that strikeout rate was a team-wide problem, with Rojas and Luke Raley the only players producing lower rates than projected, and that while the M’s rank 20th or lower in the majors in O-Swing%, Z-Swing%, O-Contact%, and Z-Contact%, they weren’t at the very bottom in any of the categories, and that the situation “has the feel of an entire team pressing in unison.”

With all that in mind, we can sympathize with the Mariners’ hitters, and better understand how only four of their 11 position players with at least 49 plate appearances thus far have a wRC+ of 100 or better, including just one of the six with at least 100 PA, namely Cal Raleigh, who hit the decisive ninth-inning homer off Josh Hader on Sunday and is batting .210/.288/.438 (111 wRC+) overall. These are some grim numbers:

Yikes. Note that five of those players have strikeout rates of 30% or higher and three more are in the 29%-30% range. What’s more, just four Mariners have a wRC+ of 100 or better at home: Rojas (222 in 49 PA), Haniger (118 in 71 PA), Garver (116 in 52 PA, despite a .156 AVG) and Polanco (107 in 77 PA). Meanwhile, Rodríguez is hitting just .233/.273/.288 (71 wRC+) at T-Mobile and Raleigh’s line there is .173/.306/.231 (76 wRC+).

Whether you’re a player or a fan, that has to be discouraging, though at least the Mariners are 11-8 at home. Given the team’s all-too-frequent status as also-rans, it’s probably not a stretch to suggest that regardless of how the Mariners win, with low-scoring or high-scoring games, with strikeouts all over the place or not, first place in the AL West will suffice.