It’s safe to say that the last week of October has never provided tennis fans with as much headline-generating news as it did in 2009. As the month drew to a close, one star, Serena Williams, patched up her reputation by showing off her finest tennis, while another, Andre Agassi, damaged his by showing off his dirtiest laundry. But while those events rightly received top billing, there was another item that caught my eye as I perused TENNIS.com. While it was considerably less sexy than a Hall-of-Famer’s dark dance with crystal meth, it was much more representative of the current ambiguous direction the sport is taking.

Here was the headline (try not to fall out of your chair): “Mercedes-Benz replaces Lexus as U.S. Open sponsor.”

What’s that? You don’t care which status-conferring luxury mobile is the “Official Vehicle of the U.S. Open”? And you call yourself a tennis fan?

Matthew Stockman/Getty Images Once a sponsor of the ATP tour, Mercedes is now focusing on the Slams.

On the one hand, this is obviously good news for tennis. The Open has secured a new sponsor, to the tune of $35 million over four years, in difficult economic times. But while Mercedes has confidence in the future of the Grand Slams and their ability to raise the company’s profile with wealthy consumers, where does that leave the rest of the tour, and by extension the rest of the sport, over the other 44 weeks of the year? The ATP can’t be too pleased to hear Cannon call the Open a “different animal” from a tour stop.

Mercedes’ perceived upgrade comes just two months after a similar shift was made by two of the sport’s American TV partners. When it made its debut broadcasts at this year’s U.S. Open, ESPN achieved its goal of covering all four majors and cemented itself as the “Grand Slam network.” Tennis Channel followed suit by making its own debut at the Open.

In the past, ESPN had ceded the Slams to the networks and centered its tennis coverage around the ATP’s Masters events. It showed multiple days of Indian Wells and Key Biscayne, and the finals from the European tournaments. All of that is gone now; ESPN couldn’t sell enough ad space during those events to make them worth their while. If they wanted to make anything out of tennis, they needed to play with the big boys.

The tours have fought back in different ways. The WTA took millions of dollars from Qatar and sent their top eight players to Doha to play in front of sparse-to-medium-sized crowds at its season-ending event. Even more crucial to the women’s tour’s future will be what happens over the next couple of months as it negotiates with its title sponsor, Sony Ericsson, on a new contract. Hopes don’t seem to be high. The ATP went in a different direction, moving its own year-end championships from Shanghai to the more publicity-friendly environs of London. The event, which is owned by the tour, was rewarded with a title sponsorship from Barclay’s. And the tour has had success branding the Masters Series as must-see tennis for serious fans.

More than ever, though, the Slams rule. Wimbledon has a new roof, the French and Australian Opens are planning vast expansions, and the deepest recession in 70 years didn’t hurt U.S. Open ticket sales. Coverage of these tournaments is more thorough than ever.

So the rich get richer, but do they take money from the middle-class in the process? Mercedes’ and ESPN’s deals with the Open validate the idea that interest in tennis is event-driven now. The quality of the sport and the charisma of its stars come second in most people’s minds to the prestige of the Grand Slams—New Yorkers don’t go to Flushing Meadows to watch tennis, they go to be part of a glamorous event called the U.S. Open.

This attitude starts with the players. Over the past 20 years, the top men and women have emphasized the Slams at the expense of the tours. Ivan Lendl and Pete Sampras started the trend by stating that the majors were what they cared about, a view that was taken to new extremes this year by Serena Williams. Prior to Doha, the No. 1 player in the world had won just two tournaments in 2009, the Australian Open and Wimbledon. There’s a trickle-down effect from there: If the players don’t care about the rest of the season, why should the fans, and why should the sponsors?

Recognizing this at the start of the decade, the USTA’s Arlen Kantarian created the U.S. Open Series. The idea was to hitch the name and the sponsorship power of the Open to the U.S. tournaments that led up to it. The Series has been a qualified success, but it had its roughest year in 2009. The top European players continued to skip the majority of it, which left its smaller events on the verge of collapse. The Legg Mason in Washington, D.C., was forced to cut its appearance-fee budget, and long-running tournaments in Indianapolis and Los Angeles said that they would need to secure title sponsors in the next two years to survive.

The Los Angeles tournament is known as “The L.A. Tennis Open.” It sounds like a pretty prestigious event. But it was almost certainly doing better under its old name: The Mercedes-Benz Cup.

Steve Tignor is the executive editor of TENNIS magazine.