Tennis is often scorned as hidebound and stodgy, unwilling to remake itself to attract the half-pipe generation. That’s nonsense, of course. Is there another sport that’s changed its most basic elements—racquets and playing surfaces—as radically as tennis has in the last three decades? But four times a year, Davis Cup provides the exception, a weekend trip into tennis’ past that’s always pleasingly surreal.

There are the ancient Anglo terms: Where did “tie,” “rubber,” and “dead rubber” come from, exactly, and where did they go? (Though I guess they’re no dorkier or more mysterious than “front-side 1080” and “triple toe loop,” two other terms I tried to make sense of this weekend.) There are the old-fashioned team introductions, where a doubles scrub is announced with the same fanfare as a Top 5 player. And there’s the sight of the game’s biggest stars being employed as courtside cheerleaders. John McEnroe was fun to watch in this position—as patriotic as he has always been, Mac could never do rah-rah.

But that didn’t stop him from heading to La Jolla, Calif., this past weekend to call the U.S. team’s win over Romania with Leif Shiras. This time McEnroe was in his best form. The spirit of Davis Cup made him more of a loose cannon than ever. His only misstep was mentioning, more than once, that he was lowering himself to announce for the Tennis Channel (and the Outdoor Life Network; the two channels split the coverage) only because of his passion for the Cup. Otherwise, McEnroe was funny and bracingly honest. He said, rightly, that Roger Federer should be “raked over the coals” for not representing his country over the weekend; that Andy Roddick had indeed “hurled” during a changeover; and that everything that’s wrong with tennis can be blamed on his old enemy Ivan Lendl, right down to the fact that the pros change their racquets too often nowadays. Yes, Johnny Mac is officially the Grandpa Simpson of tennis.

There’s one more humiliation that top players must endure when they venture into Davis Cup: debilitating nerves. As they say, there’s something about playing for your country that makes crazy things happen, and those things happened to Roddick against Andrei Pavel on Friday. As the match began, I thought there was no way that Roddick, no matter how much his confidence has sunk recently, could lose this one. While Pavel at 32 is still a strong player with one of the world’s best backhands, he has lost a step. It was just a matter of time before Roddick, nine years younger, overwhelmed him physically.

And he very nearly did, winning the first two sets and reaching match point in the third. Then the Davis Cup factor kicked in. One point from losing, Pavel hit a drop shot (he also has one of the great droppers; it could be a staple of all the textbooks) and then a topspin lob winner to stave off defeat. It was downhill from there for the U.S., as Roddick took an injury timeout for a forearm problem and then, quite publicly, got sick. Andy maintained that nerves didn’t play a role, but I can’t believe they had no effect; I’ve never see him sick on court before. To his credit, Roddick hung in and almost worked himself back into the match. (Aside: Does Roddick’s perseverance make Justine Henin-Hardenne look even worse for packing it in at the Australian Open? Yes and no. Certainly Roddick showed more guts—literally. But if he had quit, would anyone have claimed he “owed” Pavel a chance to win the match outright?)

Like his first-round loss at the U.S. Open last year, this was another nightmare come true for Andy. It wasn’t his game that failed him this time; rather, he looked like he found a way to lose. Roddick sent his forehand into Pavel’s excellent backhand at big moments and never found a way to consistently get his aging opponent on the move. I also think Roddick’s serve has become somewhat less effective as players have seen it over the years. His first delivery doesn’t generate as many easy forehands as it once did.

After James Blake and the Bryan brothers won their respective rubbers, Roddick reappeared on Sunday a chastened man. He was still feeling the effects of his stomach illness, but he also looked mentally drained. There were no fist-pumps, just slumped shoulders and a cap pulled low. Roddick rallied passively, which was enough to beat Razvan Sabau, No. 120 in the world. Still, if Sabau hadn’t gotten nervous at a few key moments, the match might have been up for grabs. It’s hard to say how Roddick would have reacted to a serious challenge on this day. With Davis Cup, though, quality doesn’t count. You know that events aren’t going to go as planned; you just want to walk away at the end of the weekend with a W. Mission—after all was said and done—accomplished.

I saw one other Cup match this weekend, Sebastien Grosjean’s straight-set revenge on Nicolas Kiefer in the rematch of their controversial Australian Open encounter. This time it was all Grosjean, and as always it was a pleasure to watch him work. Grosjean is an underappreciated talent. He has the obligatory Gallic flair, from his hopping ground strokes to the upturned brim of his backwards Lacoste cap. But Grosjean’s style is understated—I can’t think of a player who is as flashy and consistent at the same time. He also happens to have one of the all-time great forehands. He can jump and hit it with rocket-like acceleration; whip around it for an impossibly acute crosscourt angle; or take a 130-m.p.h. serve and flick it back for a blatant winner.

Tennis fans are nostalgic by nature. At our magazine, the only story idea we seem to get from readers is to do more “Where are they now” pieces. As in, what’s Jan Kodes or Cedric Pioline or Hans Gildemeister doing now? Never mind that few people would have bothered to read 10 words about these guys when they were on the tour. I can see Grosjean becoming a similar case. He’s 27 and on the downslope of his career. Appreciate him while you have the chance.