Boston Red Sox fan Danny Arelo, right, of Pawtucket, Rhode Island, jumps up as he and other fans react after the Red Sox scored in the first inning against the New York Yankees in Game 7 of the ALCS while watching the game on TV in a bar, in Boston, on October 20, 2004Steven Senne / AP

This Sunday will mark the 14th anniversary of one of the most thrilling regular-season baseball games in recent history. On July 1, 2004, the Red Sox and Yankees delivered a 13-inning epic still remembered for Manny Ramirez’s two home runs, Alex Rodriguez’s brilliant double play, John Flaherty’s walk-off hit and, most of all, Derek Jeter’s legendary dive into the Yankee Stadium stands.

At that time, the Yankees and Red Sox seemed to generate classic moments whenever they met. The previous year, in 2003, they had squared off in a dramatic American League Championship Series, full of bean balls and benches-clearing incidents, and punctuated by Grady Little’s infamous managerial gaffe and Aaron Boone’s pennant-winning home run. Months after that July 1, 2004, showdown, the teams would meet again in the ALCS, with Boston erasing a 3–0 series deficit on the way to the franchise’s first World Series title in 86 years. In 2005, the rivals tied atop the AL East. In 2006, the Yankees buried the Sox with a devastating five-game sweep in August. In 2007, the Red Sox edged the Yankees in the division race and captured another championship. In a sport hailed for its uncertainty, these two teams, and their antipathy toward each other, were a constant for the better part of a decade.

Over the coming years, however, the century-old rivalry receded a bit, as the Yankees and Red Sox seemed to alternate strong seasons, depriving fans of the excitement that came with both being good at once. At some point, the passion, intensity, and stakes of July 1, 2004, faded to memory.

But now, as the first-place Red Sox and second-place Yankees prepare for a three-game series that begins Friday in the Bronx, it feels like the mid-2000s all over again, with different names and different storylines, but similar urgency. One on side: the revitalized Yankees, managed by Boone and fueled by young stars such as Aaron Judge, Luis Severino, Gary Sanchez, and Gleyber Torres. On the other: the defending division-champ Red Sox, led by a cadre of established players, including Mookie Betts, Chris Sale, J.D. Martinez, and Craig Kimbrel.

After a close race last year, the teams entered this season looking like two of the best in MLB, and they have more than lived up to that billing. Boston surged to a 17–2 start and has maintained a torrid pace on the way to a best-in-baseball 54–27 record. New York clicked in late April and hasn’t slowed since, compiling a 52–26 mark that leaves them only a half game behind. With powerful offenses and talented pitching staffs on both sides, the AL East powerhouses appear to rank (along with the World Series champion Houston Astros) as the sport’s premier teams. They’ll spend the next three months fighting to determine who is better, then likely do it all again for several years to come.

A heated division race between archrivals always carries a certain excitement, but the stakes are particularly high in the era of MLB’s dual-wild-card system, implemented in 2012. Whereas last decade, the Yankees–Red Sox runner-up could often bank on sliding into the playoffs with a wild-card berth, this year’s second-place finisher will have to compete in a one-game playoff with the other wild-card winner just to reach the American League Division Series. One of the two rivals could very well finish with the second-best record in all of baseball and wind up fighting for its season in a do-or-die matchup against a team with a much lesser resume. The specter of the wild-card game makes winning the East far more essential than it once was—adding further drama to what would have been a compelling chase regardless.

The New York Yankees first baseman Tyler Austin (26) starts a scrum with the Boston Red Sox relief pitcher Joe Kelly (56) during the seventh inning at Fenway Park on April 11, 2018 (Winslow Townson / USA Today Sports / Reuters)

Already this season, the Red Sox and Yankees have flashed the kind of intensity that characterized the rivalry’s glory days. During an April matchup between the teams at Fenway Park, the Red Sox pitcher Joe Kelly sparked a melee when he drilled the Yankees first baseman Tyler Austin with a 98-mile-per-hour fastball, in apparent retribution for Austin’s questionable slide into second base earlier in the day. The fracas resulted in suspensions for Kelly and Austin, fines for six other players and coaches, and the sense that maybe Boston and New York players again resent each other as much as (all right, close to as much as) Boston and New York fans do.

At its best, the Yankees–Red Sox rivalry extends year-round in a way few others do. The teams have engaged in plenty of great games and tense on-field scuffles over the years, but they have also competed in offseason tugs-of-war that have shaped the dynamics between the two franchises. There was the Red Sox’s famous sale of Babe Ruth in 1920. And the trade that sent Sparky Lyle from Boston to New York just before the 1972 season. And the memorable 2003–04 offseason, when the Yankees added Alex Rodriguez, whom the Red Sox also coveted (but Boston’s acquisition of Curt Schilling wound up paying dividends more immediately).

So it felt familiar last winter when the Yankees added Giancarlo Stanton, the reigning NL MVP, and the Red Sox answered by signing J.D. Martinez, a power-hitting All-Star outfielder in his own right. And it seems appropriate, now, that the teams have been linked to many of the same impending free agents, including the superstar Orioles shortstop Manny Machado.

Of course, previous generations of the Yankees–Red Sox rivalry weren’t defined in December or July. They were distinguished in September and October, with pennants on the line. It was those fall clashes that inspired classic books, turned pinch-runners into heroes, and earned Bucky Dent his famous middle name. For this era of the New York–Boston baseball saga to match up with its predecessors, the Yanks and Sox will have to meet in the playoffs.

Last fall, the Red Sox lost to the Astros in the ALDS, preventing a postseason clash between the rivals, but this year provides brings another opportunity. Both Boston and New York are essentially locks to reach October, and if whichever of the two teams finishes second in the AL East can survive the one-game wild-card playoff, its counterpart might well be waiting in the ALDS. The Yankees–Red Sox rivalry is back, and its latest chapter has only just begun.

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