BOSTON — Though it now seems hard to fathom, there was a time — and not so long ago — when the New York Yankees weren’t the Red Sox’ most feared American League opponent.

The obsession with the Yanks — both on the part of Red Sox fans and the franchise itself — was rekindled when the teams met in the 1999 American League Championship Series, their first postseason head-to-head battle. Prior to that showdown, the ancient rivals had taken a break from their hostilities for almost 20 years.

After their epic 1978 pennant race, the rivalry cooled considerably. When the Red Sox were in contention — 1986, 1988 and 1990 — the Yankees weren’t; when the Yankees won — 1981 — the Sox were irrelevant.

Instead, the team that occupied the Red Sox’ attention for a significant chunk of the 1990s was the Cleveland Indians, the team’s opponent in this ALCS, beginning Friday night.

Three times in the span of five seasons, the teams met in the ALDS. Twice — in 1995 and 1998 — the Indians beat the Sox handily. A third postseason victory for Cleveland seemed all but certain in 1999, too, before the Red Sox rallied from a 2-0 deficit to win three straight and advance to the championship series.

The Yankees? They finished behind the Red Sox in 1995 and were themselves eliminated by the Indians in the 1997 ALDS. Though the Yankees would go on to win three consecutive championships (1998-2000) in the latter part of the decade, the Indians won two pennants — 1995 and 1997 — before ultimately failing in both attempts to bring Cleveland its first World Series title since 1954.

Then, as now, the Indians won by developing their own talent. Jim Thome, Brian Giles, Albert Belle and a young outfield slugger by the name of Manny Ramirez formed the foundation, and shrewd trades for Carlos Baerga, Kenny Lofton and Omar Vizquel helped fill in the rest of the lineup.

With a pitching staff made up mostly of veterans (including Dennis Martinez and Orel Hershiser ), the Indians overwhelmed the Red Sox in 1995, sweeping them in three games. Famously, Mo Vaughn and Jose Canseco, the heart of the Red Sox lineup, went hitless in 30 combined at-bats.

The series, however, was not without its controversy and gamesmanship, the kind that has marked the Sox-Yankee rivalry for decades. Convinced that Belle — who enjoyed a monster season with 50 homers, 126 RBI and an outrageous .690 slugging percentage in a strike-shortened 143-game season — was using a corked bat, the Red Sox insisted his bat be checked and sawed in half.

General manager Dan Duquette insisted on tweaking Belle by referring to him by his given name of Joey. Belle responded by flexing his muscles for the Red Sox.

In 1998, the Sox managed to win the first game of the series, but Cleveland stormed back to win three straight. In the deciding game of that ALDS, Jimy Williams made two controversial decisions — and only one of them worked.

Williams went with journeyman lefty Pete Schourek rather than bring ace Pedro Martinez back with just three days rest. Schourek pitched 5 1/3 innings of shutout ball and allowed just two hits.

But Williams’ other gamble failed. Deviating from form, he brought closer Tom Gordon into start the eighth inning for the first time all year and Gordon was tagged for a two-run double, erasing a 1-0 Boston lead. Cleveland won the game, 2-1, and the series, 3-1.

It looked like more of the same the following October when the Indians ripped off two straight wins to take a commanding lead in the best-of-five series. Worse, in Game One, Martinez had to come out of the game after just four innings with back and shoulder pain.

After the second loss — an 11-1 pasting by the Tribe in Cleveland — Williams, who was not given to dramatic speeches — told his players: “They’d better… sweep us.”

The message: the Indians had better not allow the Sox to crack the door open. But they did. The Sox won Game Three, 9-3, then handed the Indians one of the most lopsided losses in the history of postseason play, 23-7.

Game Five, back in Cleveland, was akin to a thrilling title fight between two boxers determined to land the knockout blow. In the first three innings, the two clubs combined for 15 runs. By the middle of the fourth inning, there had already been four lead changes.

Then, in the bottom of the fourth, the visitors’ bullpen door swung open and the night took a unimaginable turn. Martinez trotted in from the bullpen, playfully patted portly umpire Durwood Merrill on the stomach as he reached the infield and proceeded to toss six no-hit innings.

In a joyous champagne-drenched clubhouse, John Valentin climbed aboard a table and recalled his manager’s battle cry. Having failed to sweep the Sox, the Indians paid with their playoff lives.

Meanwhile, the Indians were so disappointed by the loss that they fired manager Mike Hargrove days later, despite his having directed the Indians to six straight first-place finishes in the American League Central.

Their domination over, their homegrown players grown too expensive to retain, the Indians began a period of decline, a downturn only fully reversed by this season, which saw them finish tied with the Red Sox for the best record in baseball.

Ramirez, having bolted Cleveland for the Red Sox’ eight-year, $160-million offer, is still one of the game’s most dominant hitters. Trot Nixon, who played in the final two playoff meetings for the Red Sox, is now with the Indians. Only Tim Wakefield and Kenny Lofton — who left and seemingly played for half the teams in baseball before returning to the Indians this summer — date back to the first meeting in 1995.

The Yankees, meanwhile, have been eliminated. Their manager, Joe Torre, hired weeks after the 1995 postseason concluded, may soon be dismissed.

And once more, having come full circle, the Red Sox and Indians prepare to face off in October. If it seems like old times … it is.

smcadam@projo.com