Golf, the game of graceful, soaring shots and syrupy, effortless strokes, is in reality the sport of drudgery.

This apparently sweatless, immaculate game is a taskmaster that can monopolize a man's consciousness and then invade his sleep.

Not only is the golf swing imperfectible, it is difficult even to keep it functional.

Golf's demands are stern on those who woo her: hit balls until your blisters bleed, blast trap shots until you taste sand in your meals, chip until the sun goes down, then putt on the rug until time for bed.

The rewards of this life, where every moment without a club in hand is tinged with guilt, are most vivid on the most testing courses. There, the pro's devotion to each of the 14 clubs in the bag is examined.

With which of these, the course demands of the player, have you practiced least?

Again yesterday, Congressional Country club continued this rigorous winnowing out of the PGA Tour's slackers. The men with the blisters on their hands and the callouses on their golfing souls rose toward the top in the second round of the $400,000 Kemper Open.

"Gotta get to the range 'fore dark and work on this driver," said the Kemper leader, million-dollar winner J. C. Snead -- 68-69 -- 137 -- who, under the lifelong tutelage of his uncle, Sam, has become one of the game's most respected analysts. "My left knee feels weak and wobbly at impact. I better straighten it out before I start hittin' it where I can't swing at it."

Of the nine players here who are at or under par, the common characteristic among them is a capacity for bringing enthusiasm to endless hard work.

After his Thursday morning round, Gil Morgan spent the afternoon in a deserted sand trap, blasting away while his pensive and bored caddie sat with his head in his hands.

Yesterday, Morgan ripped off a birdie-eagle-birdie streak and finished the day at 71-68 -- 139, putting him one stroke behind second-place Mike Morley, a 12-season tour journeyman who stands at 70-68 -- 138.

Tied with Morgan in third was perhaps the most famous ball-beater, sodbuster, range-rat and workaholic in golf history -- Lee Trevino, the proud owner of a 69-70 -- 139 score.

"I switched putters today, and may switch again tomorrow," said Trevino, who owns so many wands that he keeps them bound with rope at home to discourage himself from picking them up casually to experiment. That way madness lies.

"I only brought four putters with me," said Trevino, "but I've already mailed home for more. Help's on the way."

This supposedly jolly man already has next week planned. Trevino has found a secluded golf course run by friends -- Wethersfield in Hartford, Conn. -- where he can work from sunrise to sunset to prepare for the U.S. Open June 16.

"I'll get up every day at 5 a.m. The earlier a man starts, the clearer his head is," said Trevino. "Half of the practice putting green will be mowed down to Open length and smaller than usual, three-inch cups will be installed just for me.

"I'll chip and putt for three hours every day while the dew is still on the green so I can see the path of the roll of every ball," said Trevino. "I'll play, then I'll hit balls for three more hours in the evening to work on whatever is wrong."

It may be difficult to believe, but the five men tied at par -- three shots behind Jesse Snead -- constitute an even more diligent group than the four-under-par golfers. Those five are Tom Watson (71-69), Hale Irwin (74-66), John Mahaffey (68-72), Jack Newton (72-68) and Fred Marti (70-70).

Watson managed a spectacularly gritty round in which he broke par despite hitting only 10 greens. Around the carpets, he ground his gut and sweated for par like a smithy at his forge, making saves six times from traps, rough and greenside swales. Ten-foot par putts were tests of will.

The putts never ahd a chance. Watson was their master.

"Tom was superb," beamed his wife, Linda, proud of her man at his pluckiest.

"Tom will be happy and cheerful now, right?" she was asked.

"Weeeell," said the wife who has known her husband since they were 13. "More likely he'll hit a few buckets of punishment balls."

"Whenever you aren't practicing," said Watson with that firm, friendly yet somehow forbidding smile, someone else will be.I never forget that."

Locked with Watson were two other possessors of major championships who have seen different sides of the PGA work ethic.

Mahaffey has returned from the perdition of injury and 150th place on the money list in 1977 with the shame of a penitent. "I never knew what I had 'til I lost it," Mahaffey says. "If hard work will prevent it, I'll never let my game slip again."

During his long comeback, Mahaffey's bad wrist, injured at Congressional in the 1976 PGA, hurt on every shot. "I'll play as long as I can stand the pain," he said.

For Irwin, the pain of golf is finding out how to separate the compelling game from the rest of his life.

"Home is my tonic," said the Coloradan after shooting this tournament's best round so far, "When I'm away from golf, I'm away. Golf's totally forgotten. I took more time off last year than usual after winning the U.S. Open. Golf won't let you do that. What had I misplaced? Only my long game, my middle game and my short game. It's been a long time coming back."

This course wears me out," said Bob Gilder, tied with Jay Haas and Jeff Mitchell in 10th at 141. "There's not one shot where you can relax, not one shot that's just fun."

"These hard greens can be terrifying, said Irwin, one of 14 players who had sub-par rounds yesterday, compared to only seven Thursday when the field of 156 was 768 strokes over par. "The grass is so short and sparse that it's almost impossible to stop a downhill putt. The ball just rolls from one cleat hole to the next until it finally gets tired and settles in one.

"I got the shakes just watching poor Chi Chi (Rodriguez)."

What did leader Snead think of the dastardly greens?

"What greens?" he said. "I didn't see any. What I saw out there looked like Jimmy Carter's peanut patch. If it rains tonight, the water'll run off those greens like a parking lot.

"Now, Lee," said Snead, spotting his buddy, Trevino, "what I want you to do is tell 'em how great it is out there."

Congressional is great for those who understand that golf is less a game than it is a sophisticated form of suffering that can only be mitigated by the penance of practice.

Ask Dave Hill, the first round co-leader who began his day on the infamous 10th hole ("before my engine was started") and made double bogey on his way to 74.

Ask Ed Fiori who, after starting double bogey-par-double bogey, ripped off six birdies in 10 holes, only to see his day ruined by a double bogeg at the 18th hole. He threw his putter in the lake.

Or ask Morgan (the second-round PGA leader here in '76 at 66-68 -- 134) who, after his birdie-eagel-birdie streak that included an 87-yard wedge shot into the hole at the 362-yard eighth, immediately knocked a two-iron shot into the pond at the 10th and slid out of the lead.

The lesson for the 15,000 here yesterday, studying this pageant of masochism amidst the flowers, was summed up by Hill. "I truly despise my two-iron," he said, "but I keep hitting it just to see which of us will get the better of the other. You know me. Hit me in the head with a two-by-four and ask me, 'Did it hurt,' and I'll say, 'Sure. But maybe it won't next time'." Washington's Lee Elder, with a 77-72 -- 149, missed the cut by one stroke.