© 2009 MLB Advanced Media, L.P. All rights reserved.

04/23/09 10:00 AM ET

Thrill of the fight fuels Yanks-Sox rivalry

Competition at heart of what has become yearlong affair

Why is the Red Sox/Yankees rivalry so good, so intense, so anticipated, apart from the usual historical antagonism, personality clashes and dueling, gigantic fan bases? It's the competition.

The rivalry between the Boston Red Sox and the New York Yankees needs no introduction, in part because it never seems to leave the stage.

It's a 12-month arrangement now, what with the offseason wheeling and dealing, not to mention the carping and complaining and occasional name-calling. But the portion of the rivalry that the rest of us wait for begins anew on Friday night at Fenway Park.

This is the opening of a three-game series, but that is only the opening of an 18-game regular-season series that will carry the clubs to the last weekend in September. And then, of course, the possibility always exists of a meeting in the American League Championship Series, which brings to mind the October epics of 2003 and 2004.

The Red Sox, historically the supporting players in this drama, the victims, the foils, have changed all that in this new millennium. They are the only Major League Baseball team to have won two World Series championships in this century. This puts them, in that period of time, two World Series championships ahead of the Yankees. That sort of thing just makes the championship drought in the Bronx that much more difficult to take.

But when these two clubs face each other, the playing field is very close to level. Over the last seven regular seasons, the Yankees lead the series, 68-63.

The biggest season spread in that period was merely 11-8. Three times the series has been decided by a 10-9 margin, and once it was tied. Overall, the Yankees have won five of the last seven season series.

Beating the Red Sox in a season series, in a year in which the Red Sox win the World Series, such as 2007, is not much consolation for the Yankees. But it is a good measurement of how competitive this rivalry is.

Consider, for instance, the Red Sox against the remainder of the AL East. In that same seven-year span, the Red Sox lost one season series to the Orioles, one season series to the Rays and two season series to the Blue Jays.

This rivalry is not just hype. It is the real deal, on the field; close, competitive, compelling.

The rivalry remains constant in a way, but within that context, there are always new elements and alterations, new twists and turns. The Yankees, out of the postseason in 2008 for the first time since the middle of the last decade of the last century, did over the winters what only they can do, spending $423.5 million on three free agents.

The pressure will be substantial on those three otherwise fortunate fellows -- CC Sabathia, A.J. Burnett and Mark Teixeira -- but it will never be more substantial than when the Yankees are playing the Red Sox. There are true tests for new Yankees, and there are truer tests, and then there are truest tests, such as this one.

The Red Sox have changed, too, over the years, but in a more evolutionary way. The 2009 Boston team has a composition that is dramatically different from the 2004 championship team, because it is a pitching and defense-first operation. And it needs to be, with no more Manny Ramirez as a middle-of-the-order mainstay.

The Yankees will be without Alex Rodriguez for these three games, as he recovers from hip surgery. For Red Sox fans, A-Rod has been a convenient embodiment of everything that they believe is wrong about the Yankees. His absence will be noted, but the series will go on as scheduled, weather permitting.

Adding more fuel to the rivalry, even though no more fuel was required, is the fact that the competitive landscape in which these two clubs operated has become even less forgiving than usual.

Last season in the AL East, true, the Yankees were third, but the Red Sox were merely second. The best team by record was Tampa Bay. Even though the Rays are off to a slow start in 2009, nobody should seriously believe that this young and exceptionally talented team was anything like a fluke.

So here are the Yankees and the Red Sox, again, still, yet, one more time. This is unlike a lot of rivalries because here, the reality is even better than the rhetoric.

Mike Bauman is a national columnist for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.