NEW YORK (Interstat) — In a stunning reversal of pregame expectations, the Boston Red Sox, powered by a dominant pitching performance from Garrett Crochet and a clutch hit from pinch-hitter Masataka Yoshida, seized the opener of their American League playoff series with a 3-1 victory over the New York Yankees on Tuesday night at Yankee Stadium.

A sold-out crowd of 47,027 watched as the Red Sox, heavy underdogs according to statistical models, methodically dismantled the Yankees’ pitching staff late to take a 1-0 series lead. The game, which lasted 3 hours and 4 minutes, was a tense, pitcher-dominated affair for six innings before Boston’s offense finally broke through.

The contest was a stark departure from the projections. Interstat’s game simulator had forecast a 7-6 Yankees victory, and its ELO system gave New York a 57 percent probability to win. The Yankees had also been installed as pregame favorites with a -1.5 spread. Instead, the teams combined for only four total runs, falling well under the over/under line of 7.

The story of the night was Boston’s pitching, specifically the left arm of Garrett Crochet. The winning pitcher was magnificent, baffling Yankees hitters over 7 2/3 innings. He allowed just one run on four hits while striking out 11, relentlessly attacking the strike zone and neutralizing the heart of New York’s powerful lineup. The lone blemish on his line was a solo home run by Anthony Volpe in the bottom of the second inning that gave the Yankees an early 1-0 lead.

That lead was protected masterfully by Yankees starter Max Fried, who matched Crochet zero for zero through six scoreless frames. Fried scattered four hits and struck out six, exiting the game in the seventh inning with a runner on first and a one-run lead. He was relieved by Luke Weaver, who was promptly charged with the loss.

The game’s pivotal moment arrived in the top of the seventh. After Jarren Duran grounded out, Ceddanne Rafaela worked a walk against Fried, prompting the pitching change. Nick Sogard then greeted Weaver with a ground ball double down the right field line, advancing Rafaela to third. With the tying and go-ahead runs in scoring position, Boston manager Alex Cora called upon Masataka Yoshida to pinch-hit.

Yoshida delivered immediately, lacing a single into center field that easily scored both Rafaela and Sogard, flipping the score to 2-1 in favor of the Red Sox. The hit electrified the visiting dugout and silenced the Bronx crowd, completely shifting the momentum of the game.

Boston added a critical insurance run in the top of the ninth against Yankees reliever David Bednar. Trevor Story sparked the rally with a single to left field. Alex Bregman, who had two of Boston’s eight hits, then provided the exclamation point, drilling a sharp line drive double into the left field corner that allowed Story to race home from first, extending the lead to 3-1.

The bottom of the ninth provided a final, heart-pounding threat from the Yankees. Facing Boston closer Aroldis Chapman, Paul Goldschmidt and Aaron Judge led off the inning with back-to-back singles. Cody Bellinger followed with another single to load the bases with nobody out, bringing the winning run to the plate and sending the stadium into a frenzy.

With the game on the line, Chapman bore down. He struck out the dangerous Giancarlo Stanton swinging for the first out. He then induced a fly out to right field from Jazz Chisholm Jr., which was not deep enough to score a run. Needing just one more out, Chapman fired a series of blistering fastballs to Trent Grisham, eventually striking him out on a foul tip to end the game, stranding the bases loaded and securing his 33rd save of the season.

Chapman’s final line was 1 1/3 innings pitched, three hits allowed, no runs and two crucial strikeouts.

For the Yankees, the defeat was a frustrating start to the postseason. Volpe’s second-inning homer accounted for their only run, as they went 0 for 4 with runners in scoring position and left seven men on base. Their bullpen, a strength for much of the season, faltered at a critical juncture.

With the win, Boston improved its season record to 90-73, while the Yankees fell to 94-69. The Red Sox now hold a commanding position in the best-of-five series.

The two rivals will reconvene at Yankee Stadium on Wednesday for Game 2. The Red Sox will look to take a stranglehold on the series before it shifts to Boston, while the Yankees will be desperate to even the score and avoid falling into an 0-2 hole.