The men’s tennis tour officially ended its round-robin experiment last week — a wise and praiseworthy decision considering the recent debacle in Las Vegas that left James Blake out, then in, then out of a tournament. Perhaps now it would consider scrapping its ill-advised plan to dispose of best-offive-set finals.

The five-set ban, which goes into full effect next season, will not apply to Grand Slam tournaments or Davis Cup matches but to all other events except the year-end Masters Cup. At the Sony Ericsson Open in Miami this week, the finalists will play the only best-of-five-set match in the regular season. Last year, 14 ATP tournaments asked their finalists (and only their finalists) to play best-of-five; in 2005, 13 tournaments did so.

Those tournaments produced, by my count, at least seven superb matches, the kind you might consider buying on video if you missed them the first time around. In one (the 2005 Nasdaq final), Roger Federer lost the first two sets to Rafael Nadal and then came back to win. In another (2005 in Madrid), Nadal fought back from two sets down against Ivan Ljubicic. Another two-sets-to-love comeback displayed David Nalbandian at his finest as he toppled Federer in the 2005 Masters Cup final.

Five-set finals recently have treated one city, Rome, better than any other. The Italian capital hosted two thrillers in 2005 and 2006, both of them among the best examples of clay-court tennis in the last two decades. Nadal won both, first in five sets over Guillermo Coria after trailing 3–0 in the fifth set in the 2005 final, and last year over Federer after trailing 4–1 in the fifth set and facing two match points. The Nadal-Federer match not only had tension and drama, but supreme artistry: It’s the best Federer has ever played on clay (his slices, volleys, and footwork created an astounding contrast to Nadal’s heavy topspin and relentless hustle).

So why would the ATP want to do away with five-set finals when they often produce a great product? Ostensibly, for the good of the players. The tennis season runs from January through November, and the thinking is that doing away with five-set finals will prevent injuries. Another reason is the belief that they last too long and are less interesting to young and casual tennis fans (the tour wants more and more of those; the die-hards are a lock no matter what the format, the thinking goes).

Both of those reasons are wrongheaded.

The fatigue excuse, while convenient and appealing upon first glance, has no basis in fact. There’s no medical evidence that playing one five-set match after a week’s worth of best-of-three-set matches significantly increases the chance of injury. The ATP last year said it would impanel a group of doctors to examine the possible causes of tennis injuries: back-toback tournaments, back-to-back days, total length of the season, composition of playing surfaces, changes in technique, equipment, etc. There’s been no report since the announcement, and certainly nothing to indicate that playing five sets is particularly dangerous, especially when it’s done in moderation.

Some of you might recall that last year’s Rome final, as wonderful as it was, killed the follow-up tournament in Hamburg (both Federer and Nadal felt so taxed after five hours of tennis on Sunday that they pulled out of Hamburg, which began on Monday). But if that final had been best-of-three sets, the two still wouldn’t have traveled to Germany. The problem was that neither wanted to play 12 out of 14 days right before the French Open, not that they had played five sets. Two Masters events held in backto-back weeks was to blame, not the length of the final.

The Sony Ericsson Open (formerly sponsored by Nasdaq) and its companion tournament, the Pacific Life Open, which ended last weekend, don’t have this problem. Nadal won the Pacific Life in two sets over Novak Djokovic; if he had needed five sets, he would not have skipped this week’s Sony Ericsson because he had four days to rest before his first match (I’m willing to bet that Nadal vs. Djokovic would have been a better contest in a best-of-five format, as the 19-year-old Djokovic was just finding his game when he lost). These two tournaments have adequate spacing before them, between them, and after them. Considering the chaos of the tennis schedule, March is perhaps the most efficiently constructed month. There’s no need to tinker with one of the few areas of the season that works perfectly.

Unless, that is, you believe that fans do not want to watch five-set finals. At the Australian Open, the ATP’s chairman, Etienne de Villiers, told a group of reporters that he “took the dog for a walk after the third set” of Federer vs. Nadal in Rome. De Villiers said he knew he could return in an hour’s time to catch the best hour and a half of tennis he had ever seen, without losing anything in the process. While this may be true to some degree, if the match had been bestof-three sets, like it will be this year, there would have been nothing left upon his return. Could the third set, as the final set, have been as good as the fifth set? Yes, but it’s not likely. Oftentimes fifth sets are better not because players hit superior shots, but because of the four sets that have preceded them. History and tension inform a match; the more, the better.

It’s reasonable for de Villiers and the ATP to fear the effect longer matches will have on the popularity of tennis. But it’s not as if all fiveset finals require a full five sets, or last longer than five hours, as did the two Rome finals. In 2005, the average length of these 13 matches was four sets, with five of 13 matches going the distance. Last year, it was 3.4 sets with two of 14 going the distance. Remarkably, this ban was not the idea of television broadcasters, either. CBS, which televises the Sony Ericsson final, wants it to remain five sets because that’s what it agreed to under the terms of its contract. You can’t fault CBS for thinking it will now receive less product for its dollar. If the ATP chucks five-set finals into the dustbin, the rest of us will have been cheated too.

tperrotta@nysun.com