Last year John McEnroe came to Wimbledon for the first time as an anonymous 18-year-old qualifier and left a celebrity, the youngest semi-finalist in the 100-year history of the most ancient and celebrated of tennis tournaments.

The fates showed the talented, temperamental and supremely self-confident left-hander from Douglasston, N.Y. that they can frown as well as smile yesterday.

Now ranked among the top 15 players in the world, seeded No. 11 in Wimbledon's 101st year, McEnroe became a 19-year-old first round loser, beaten by the inspired Erik van Dillen - the expected wunderkind of an earlier generation who never approached the heights forecast for him - 7-5, 1-6, 8-9, 6-4, 6-3.

That was probably the most interesting of a feast of fascinating matches that kept the All England Lawn Tennis and Croquet Club bubbling and bustling through a long day's journey into twilight.

Less satisfying esthetically, but just as poignant in the end, was 1975 champion Arthur Ashe's five-set demise at dusk to Steve Docherty, a 6-foot-5 Australian who played defensive end on the Washington State University football team in 1970, took up residence in Oregon after graduation, and now holds the No. 33 ranking in the U.S.

This was strictly a serving contest on the bumpy grass of Court 14, out by the water tower in the futhermost cornor of the grounds from the Center Court where Ashe, then 32, triumphed over Jimmy Connors in the final three years ago.

There was only five service breaks in a match that lasted well over three hours and had no rythm, only thumping percussion.

Finally at 5-5 in the fifth set, with daylight fading and the grass getting slippery, the muscular Docherty clubbed three mighty sevice returns and a forehand cross-court passing shot to break Ashe at love, then served out his 8-9, 9-8, 6-3, 5-7, 7-5 victory.

"I tried as hard as I could, but the guy just served unbelievably well.The scores attest to the fact that neither of us could do anything but serve and pray," sighed Ashe, who stayed on court for 20 minutes, despite his obvious dejection, and signed autographs.

%I don't usually dot that, but I figured what the heck, it's over, finished," he said. "I just sat out there and didn't feel much of anything.

"It's a pretty big blow because you key your whole year around this one tournament. Then to go down to an ignominious defeat in the first round, 7-5 in the fifth, on Court 14 . . ." His voice trailed off, his face a portrait of disappointment and introspection. "What can I do? Just come back next year and try again."

Two other former champions - Stan Smith (1972) and Jan Kodes (1973) - were also beaten, while another, John Newcombe (1967-70-7), struggled but survived to another day.

The only one of the women's seeds who lost a set yesterday was 15-year-old Tracy Austin, who had some anxious moments before beating Diane Desfor, 6-1, 6-8, 6-4.

Smith did not prove nearly as troublesome as expected for the No. 4 seed, 1977 French and U.S. Open champion Guillermo Vilas, who prevailed on Court, 6-4, 6-3, 6-3.

Smith did not have much conviction in his once awesome serve-and-volley attack, and the Argentinian left-hander passed him repeatedly with the sort of consistent grounds stroking seldom seen on a grass court.

"It was like the Charge of the Light Brigade. Smith kept rushing the net and getting shot to pieces," one court-side observer noted, summing up the match neatly. "Vilas made it seem as if there were acres of court on either side of him, despite his long reach."

Kodes, the Czech who won in the year of the boycott by members of the Association of Tennis Professionals retired with an ankle injury at 0-2 in the third set after having lost the first to Chilean Davis Cupper Jaime Fillol, 6-2, 6-1.

Newcombe, the last of the 16 seeded men, was down a set and 4-5 to qualifier Dale Collings, a beefy fellow Australian with afiery temper to match his flaming red hair and mustache, but cracked four clean return winners of Collings' formidable serve to keep from falling behind two sets to love.

Newcombe came back to win, 4-6, 7-5, 7-5, 6-3, but recognized what he has been reluctant to admit in recent months, after optimistically launching a comeback bid at the start of the year - that he is not really a threat for the fourth Wimbledon singles title he wanted so badly.

"I was lucky to get through today," he said. "What helps you when you come to Wimbledon is having won tournaments beforehand. You need a track record behind you so you know at 15-30 that you're going to get your first serve in instead of just hoping you do. That's where I'm behind the eight ball. I haven't found my form all year. It would be surprise if I did anything here.*

Unlike Ashe, he does not plan to try next year. "I've had my run. I wouldn't like to play the singles here unless I thought I had a real chance to win. That takes a lot of preparation," he said.

Newcombe's old friend and partner in four doubles titles here, Tony Roche, was beaten by fellow Aussie Phil Dent, 6-4, 7-5, 4-6, 7-5, in a forthright match thatearned a long standing ovation from the crowd around court No. 1.

Roche, a year younger than Newcombe at 33 and runner-up to Rod Laver here 10 years ago, had shown glimpses of his old form in winning last week's Grand Prix tournament at Queen's Club, beating McEnroe in the final on Sunday.

But when it came to the crunch, at 4-5 in the final set, Dent delevered three clean aces and unreturnble serve: Then Roche double-faulted, made a bad volley error to fall 15-40 down, and Dent lashed a forehand passing shot on the dead run for the break that decided the match.

The more realistic contenders - No. 5 seed Brian Gottfried and No. 6 Roscoe Tanner - escaped thorny positions.

Gottfied completed a 6-1, 6-8, 8-6, 6-4 truimph over Englishman John Lloyd, runner-up in the Australian Open on grass last December. Gottfried recovered from 0-3 in the fourth set with some outstanding returns, much as he had from 2-5 in the third set before their Center Court encounter was halted by darkness Monday evening.

Tanner lost the first two sets to Egyptian left-hander Ismail El Shafei and was down 0-30 at 7-7 in the fourth set, but his vaunted serve was there when he needed it most. He served two aces in climbing out of that hole and won, 8-9, 1-6, 6-2, 9-7, 6-2.