“Roger is nowhere near where I was before I won my last major (at the 2002 U.S. Open). I was a mess. I was pretty lost, looking at different coaches, not really feeling great about my game. I’m not worried about Roger. He has to take care of his body, but I’m not worried about him tennis-wise. He seems really motivated to play all these events, I don’t even know where he gets that. But he could be around until he’s 33, 34, maybe even more.”Pete Sampras, in a conference call today to promote the Greenbriar Champions’ Tennis Classic.

We all know that tennis is a “what have you done for me lately?” kind of sport, which explains why even if we don’t like to admit the fact, it’s pretty easy to move on and find diversion elsewhere when a player — even a favorite — retires, or takes time off for injury or rest. Rafael Nadal, who took off to deal with injury for the last seven months of 2013 knows that, and Roger Federer knows it too.

We last saw Federer at Indian Wells, back in mid-March. We won’t be seeing him again until the second clay-court Masters 1000, in Madrid. He’s played just 17 matches this year, roughly half the number logged by world No. 1 Novak Djokovic. The combination of this low profile and his age (he’s going on 32) makes it pretty tempting to overlook him as a potential force this year.

But. . .did you notice how he lost his No. 2 ranking to Andy Murray a few weeks ago, but has now recaptured it thanks to Murray’s subpar performance in Monte Carlo? Perhaps it’s an omen.

When Federer returns to the tour in Madrid, it will be with a replenished mind and fresh legs. Some people think he’s just asking for trouble, returning to competition after a layoff of nearly two months at a high-octane Masters 1000 event, but something tells me that Federer is thinking two or three moves ahead.

Granted, he’s the defending champion in Madrid (d. Berdych in the final), but that was on the smurf (blue) clay that caused such a brouhaha in the ranks of the ATP. Madrid has returned to the familiar, traditional red clay for this year, and that recalibrates the odds in favor of Rafael Nadal and Novak Djokovic.

Federer last beat Nadal on the Madrid clay in 2009, and while he did put up a sensational win over Djokovic to halt his 2011 winning streak at Roland Garros, Djokovic handled him convincingly in the semis at the same venue last year. And as fit and hard-working as Federer is, age is not his ally at this stage of his career.

Given all this, I believe Federer is willing to take all he can get out of the Euro-clay circuit, but suspect he’s not going to get all broken up if it doesn’t work out for him in Madrid, Rome, or Paris. His real hole card is Wimbledon, where he’s defending champ and, owing to his style and fitness profile, worthy of as much respect and fear as any of his younger rivals. I have to think Federer is looking at the clay-court circuit as a way to bank valuable rankings points, but also — and perhaps more important — as a way to play his way into fighting shape for the defense of his Wimbledon title.

Federer’s most important mission in the coming months — and years, if Sampras is right — will be to win enough matches to keep his ranking high enough to earn him a high seeding. That reality highlights an enormous dilemma, and an unappealing feature of the otherwise excellent ATP ranking/seeding system. Federer can play any tournament he wants no matter where his ranking goes in the foreseeable future thanks to the wild card provision. But there’s no seeding wild card.

The further Federer’s ranking falls, the tougher it will be for him to compete, no matter how proficient he remains on some surfaces. And Fedrerer will be defending over two thousand rankings points on clay in the coming weeks. He has his work cut out.

Sampras was ranked No. 17 when he won his 14th and final major at the U.S. Open, more than two years after his last previous Grand Slam title (Wimbledon, 2000). But he started 2002 ranked No. 10, and had started 2001 ranked No. 3. Sampras suggests that Federer’s decline may not be as precipitous as was his own, but the system isn’t kind to aging players, and the numbers that attended Sampras’s final two years aren’t encouraging.

Sampras was the same age (31) when he won his final major as Federer will be at Wimbledon this year. Is it possible that Federer wins the tournament and calls it quits, as Sampras did? It’s unlikely, but it’s becoming a numbers game for Federer, and unfortunately the number 17 (the tally of his Grand Slam singles titles) isn’t the one that counts.