After an initial viewing of yesterday’s final at the Monte Carlo Masters, where Rafael Nadal ran his clay-court record against Roger Federer to 5–0 with a 6–4, 6–4 victory, I was tempted to attribute this unsurprising outcome to unsurprising causes: Nadal’s steadiness, Federer’s unwillingness to slice his backhand and approach the net and an erratic Federer forehand.

Tennis, perhaps more so than other sports, benefits from a second look. The ball can mesmerize as it travels back and forth across the net, and obscure subtleties, especially how players position themselves and how often they opt for depth rather than sharp angles. So it was that yesterday’s final seemed a display of bad tactics, mistimed strokes, and declining confidence by Federer.

If this were so, Federer could consider it good news. These days he is without doubt the secondbest clay-court player in the world, and he does not adjust to the surface as quickly as Nadal. He also hasn’t played much lately, either, owing to two surprise losses on hard courts to Guillermo Canas. Yet he did not lose a set in reaching the Monte Carlo final for the second consecutive year. In the month leading up to the French Open, there would be plenty of time to catch Nadal, perfect his timing, steady his service returns, and play more volleys, as he did in Rome last year when he held two match points against Nadal before losing.

Unfortunately for Federer, optimism is not in order. One would not expect a man who has won 62 consecutive matches on clay, as Nadal had before this tournament began, to fiddle with his game. But the 20-year-old Nadal has. The difference is the improved depth of his shots — a slight adjustment, yes, but if he can sustain it, he’ll arrive at the French Open a better clay-court player than he was last year.

First consider the conditions at this event. Players and commentators agreed all week that the Monte Carlo courts, baked by the sun, played quickly — undoubtedly an advantage for Federer. In the early going yesterday, Federer took the offensive, approaching the net five times in the first game and nearly capitalizing on a few uncharacteristic Nadal errors to break serve in the second game. Federer had two more break points in the eighth game, but his forehand went awry. From the end of this game to the end of the next, when he lost his serve, Federer made seven errors in eight points.

Many of these errors looked bad, but Nadal had more to do with them than it seems. While the Spaniard hardly played his best overall match yesterday, he hit the ball deep into the court more consistently than he ever has against Federer on clay. The depth of his shots allowed him to challenge Federer’s forehand more than usual, a change in tactics Nadal highlighted in his post-match press conference.

In all their previous meetings on clay, Nadal won because of brilliant defense. Although he often gave Federer a lot of chances in the forecourt, especially in Rome, his feet saved him from defeat. Yesterday, Federer’s chances were few. It might have seemed that he should have charged the net more often, but a replay of the match showed only three or four chances in which he could have made a lessthan-foolish approach and did not. He spent most of the match just as far behind the baseline as Nadal.

What about his slice backhand? Early on, Federer did try a few, and he hit two brilliant slice lobs, too (one for a winner, and one that he should have followed to the net and did not; that cost him a point). But he abandoned the slice late in the first set, and for good reason: Nadal wasn’t the least bit concerned by it. Although Federer’s slice at times lacks bite, it often arrives at such an extreme angle that it forces his opponents out of position. Federer hit one of those yesterday; the ball bounced on the clay and sat up as Nadal charged it and smashed a forehand winner. Federer’s topspin backhand, usually the cause of many shanks and shouts, was his best shot yesterday (perhaps the one promising sign for Federer fans). He was right to stick with it.

In the last year, Nadal has tried to adapt his game to hard courts and grass. That work seems as if it will pay dividends on clay, too. Nadal missed more forehands than usual in the first set yesterday, but he went for more than usual: It was only two years ago, in the Rome Masters final, that Nadal was pushed around for five sets by Guillermo Coria, who is generously listed at 5-foot-9 and 152 pounds. Nadal won, but Coria played the role of bully, Nadal’s bulging biceps not withstanding. In the second set yesterday, Nadal controlled a healthy majority of rallies and didn’t face a break point.

What’s Federer to do? Moving forward remains the best plan of attack, but the most important improvement Federer can make is on his return of serve. Federer’s chief talent on returns is putting balls in play — no matter how fast or how well spun the serve, it rarely gets past the world no.1 (compare this with Andre Agassi, who gave up a lot of aces, but unloaded on the ball when given the chance). Federer’s returns work well against someone like Andy Roddick, but not Nadal. The Spaniard served 79% on first serves yesterday, and admitted he was “serving slowly” (Nadal served terribly in his semifinal match against Tomas Berdych, so he practiced for a halfhour afterward).

When they meet again this clay court season — and it wouldn’t be a wise bet to say they won’t — Federer can’t let Nadal get away with this. If he does, the all-time best clay-court winning streak, now at 67 matches, might live to see Monte Carlo next year.

tperrotta@nysun.com