Curt Schilling aggravated his right ankle injury while starting Game 1 of the Red Sox's division series against the Angels and was fitted for a brace prior to starting Game 1 of Boston's American League Championship Series against the Yankees. However, the injury was not a major source of concern heading in to the game, because RHP Schilling basically had been pitching with the problem all year and his performance did not suffer in the second half of the season.

RHP Mike Mussina went one-two-three through the Boston order in the top of the first, bringing Schilling to the mound. His initial pitches seemed very deliberate, and with the count 3-2 on 3B-R Alex Rodriguez, he stopped to retie his right shoe. Like SS-R Derek Jeter before him, ARod hit a catchable fly ball into the outfield. RF-R Gary Sheffield was less obliging, hitting a line drive down the left field line for a double. LF-L Hideki Matsui then dropped a flyball into left center, where neither LF-R Manny Ramirez nor CF-L Johnny Damon was able to catch it. Sheffield scored on Matsui's double. CF-S Bernie Williams knocked a groundball through the right side of the infield for a single that drove in Matsui, and New York left the first inning with a 2-0 lead over the Red Sox.

Schilling seemed to recover somewhat in the second and like Mussina only faced three batters that inning. After the top of the third, the fact that Mussina was pitching a perfect game began to take on more weight. In contrast, Schilling allowed a leadoff single to Jeter. ARod also singled, and Schilling walked Sheffield to load the bases. Following the walk, Schilling again was shown retying his right shoe. Matsui hit a flyball down the right field line, scoring all three base runners. That prompted Boston to send pitching coach Dave Wallace out to the mound while LHP Mike Myers got up in the pen. Williams then grounded out to the right side of the infield, allowing Matsui to advance to third and putting him in position to score when C-S Jorge Posada hit a sac fly into center. Schilling went on to walk 1B-L John Olerud, but 2B-R Miguel Cairo hit a catchable fly to deep center to get Schilling out of the inning.

Mussina struck out the side in the top of the fourth.

In the bottom of the fourth, RHP Curt Leskanic took the mound in place of Schilling and managed to hold the Yankees to their 6-0 lead despite starting the inning by issuing walks to DH-L Kenny Lofton and Jeter. Mussina struck out two more in the fifth and kept his perfect game going. RHP Ramiro Mendoza went out to the mound for the Red Sox, hit Posada in the knee with a pitch, and allowed Olerud to single, but kept New York from scoring.

With Mussina still perfect through six, Lofton led off the bottom of the inning with a home run down the right field line off of new pitcher RHP Tim Wakefield. Later in the inning, Sheffield doubled and was driven in by a Matsui single, expanding the Yankees' lead to 8-0.

Mussina led off the seventh with his eighth strikeout of the night, but 2B-S Mark Bellhorn broke up both the perfect game and the no-hitter, hitting a long flyball to the left field fence for a double. Ramirez grounded out, but with perfection undone, the rest of the Boston lineup woke up. DH-L David Ortiz hit a line drive into right field for a single, moving Bellhorn to third. 1B-R Kevin Millar then sent a flyball over Matsui's head for a double that drove in both Bellhorn and Ortiz. Mussina's first pitch to RF-L Trot Nixon bounced off Posada's chest protector, allowing Millar to advance to third. Millar scored when Nixon hit a line drive into shallow center for a single, prompting New York to replace Mussina with RHP Tanyon Sturtze. C-S Jason Varitek boosted a pitch into the right field stands for a two-run homer before Sturtze struck out SS-R Orlando Cabrera to end the Red Sox's rally.

With the score 8-5, LHP Alan Embree took the mound for Boston and prevented the Yankees from cushioning their lead. Prior to the eighth, RHP Tom Gordon relieved Sturtze. Cairo made a diving stop of 3B-S Bill Mueller's leadoff grounder, but the ball rolled out of his glove before he could attempt a throw to first. Later in the inning, Ramirez dropped a flyball into shallow left center, advancing Mueller to third. Both Mueller and Ramirez scored when Ortiz sent a flyball to the warning track, where Matsui failed to catch it and almost tipped it over the wall. The ball rolled away down the outfield wall towards center, giving Ortiz time to reach third. New York responded by bringing in RHP Mariano Rivera to relieve Gordon. Rivera secured the final out of the inning without allowing any further scoring, so Boston was still one-run short of the Yankees going into the bottom of the eighth.

Before New York came to bat, RHP Mike Timlin relieved Embree. Timlin obtained two outs but gave up singles to ARod and Sheffield before Williams came to the plate. Williams hit a fly ball over the head of Ramirez, which enabled both base runners to score while Williams safely took third. The Red Sox then replaced Timlin with RHP Keith Foulke, who closed out the inning without permitting the Yankees to score again. Boston failed to push across even one of the three runs the Red Sox needed to tie the game in the top of the ninth, so New York took Game 1 by a score of 10-7.