When Jack Nicklaus plays the way he did today at the Augusta National Golf Club, he almost looks like part of the majestic landscape -- as imposing, elegant and downright venerable as the Masters tournament itself.

Nicklaus shot a peculiar 65 today -- strange because he birdied only one par-5 -- for a 36-hole score of 135, nine under par, and a four-stroke lead over Tom Watson, Lon Hinkle, Bruce Lietzke and Australian Greg Norman at the midpoint of this 45th Masters.

But what made the day memorable had more to do with style and bearing than with mere numbers. Nicklaus went out on a lazy, hazy Georgia morning and took it over, making it crackle with electricity and echo with the roars of a gallery that grew steadily in size and excitement. By noontime the haze had burned off, and the day and Nicklaus were both torrid.

He holed putts of one, 20, 17, and 20 feet for consecutive birdies on the fourth through seventh holes, hardly the section of the lovely Augusta National terrain where low rounds usually take shape.

That got adrenaline flowing as fast as perspiration, both the crowd's and Nicklaus', but this was more than just a hot putting round. For two days, Nicklaus had been striking the ball superbly, crushing his drives, hitting boldly for the pins, making the devil's game look easy.

He missed the green on the first three holes of the back nine ("I got a little sloppy there"), but saved pars by putting the way he used to and chipping better than he ever has. Pumped up again, he made birdies on 13, 14, and 16 without a putt of more than four feet.

On the 18th he saved par once more, carressing a little chip shot over a ridge from about 70 feet to the right of the hole. It broke sharply and curled up to the hole as if guided by radar, stopping six inches short for a top-in putt: his 11th one-putt green of the day.

By this time, Nicklaus as if he were a permanent and hallowed part of Augusta National, site of five of his record 19 major tournament triumphs. He seemed to belong here, as much as the pines and azaleas and the throngs who followed him on a day that smelled of suntan lotion and flowers.

Today's 65 was the second best score Nicklaus has ever had in the Masters, one stroke off the course record he equaled in 1965, and shares with Lloyd Mangrum, Maurice Bembridge, Hale Irwin, Gary Player and Miller Barber.

"The course plays much longer now, though," reminded the owner of a record five of the green coats that go to the Masters champion. All factors considered, he figures his first two rounds may be the best ball-striking 36 holes he has played at Augusta.

Nicklaus insisted that he didn't play as well today as Thursday, when he shot 70. Then he was cautious and frustrated in his putting, but flawless from tee to green. "That was the best round I have ever seen played," said his first-day partner, Australian David Graham, who is tied with Hubert Green at 140 (70-70), five strokes off the lead.

"Both days I've been very relaxed, very confident, I haven't been jumpy over the ball. I haven't been apprehensive over any shot. I felt I could hit almost anything at the flagstick," said Nicklaus, who has had 11 birdies and no bogeys in his last 33 holes.

"When you feel that way, you hope you can make a few putts, too. Yesterday I didn't. Today I did . . . The pin positions on a lot of holes allowed you to be more aggressive, and I was."

Nicklaus' dominating performance overshadowed everything else today, as the starting field of 82 was pared to the 48 players who shot 148 or better.

Severiano Ballesteros of Spain (78-76 -- 154) became only the third defending champion to fail to make the cut. (The others were Nicklaus in 1967 and Tommy Aaron in 1974.) Lee Elder of Washington, D.C., (77-73 -- 150) was another casualty.

Nicklaus went out early in the day, and put his birdie streak on the board for the other contenders to shoot at, or be intimidated by. Watson and Norman got within three strokes, at six under par, but bogeyed the 17th and 18th, respectively.

Lietzke birdied the 13th, 14th and 17th to take a share of second place, but said he doesn't like his chances because his normally sure putting stroke is a shambles, and messing up his mind.

Hinkle, who shared the first-day lead with Norman, Johnny Miller and Curtis Strange, birdied the 15th and 18th today to finish strongly, but said "there are a lot of people I'd rather be chasing than Jack." Miller was tied for second until he bogeyed the last two holes, while Strange put a 79 with his opening 69 and barely made the cut.

No one was ready to declare the tournament over, including Nicklaus. "I have no idea what the final score will be," he said. "I hope I can shoot two more good rounds, because if I don't I'm not going to win."

Watson, who pull-hooked his drives on the last two holes ("I tried to hit the ball too hard, and just made bad swings"), acknowledged that a four-stroke lead is not that big, but that it seems bigger when it belongs to Nicklaus.

"When you're four shots behind, you have to make fewer mistakes than the guy who's in front, and the way Jack has been playing, he isn't making many mistakes," said Watson.

Meanwhile Nicklaus, clearly tickled with the way he is playing, can taste his 20th major title at age 41. "I've said many times, I'm sure my record for major championships will be broken somewhere along the line, but I want to make sure before I hang it up that the guy who does it has to win a whole bunch of them," he said.

He was asked if there is any special magic in the number 20, as it relates to majors.

"Yeah," said Nicklaus with a smile, "my next one."