Seve Ballesteros, who missed the Kemper Open cut by one shot, returned to the TPC course at Avenel yesterday and said the chances are good he will play the Kemper again soon. "It's very possible, if the dates are the same," he said after hitting some practice balls and lunching at the club.

He tried to use the Kemper as a tuneup for the U.S. Open two weeks hence at Medinah, near Chicago.

Ballesteros, three-time British Open and two time Masters winner and the biggest Kemper name, said of his showing here: "The toughest thing was I never really had my momentum."

He said one of the keys was a first-round double bogey at the relatively easy par-5 sixth hole, (his 15th), on which he dumped a sand-wedge shot into a creek. "I was looking at two under and I left the hole one over," he said. He said another pivotal point was the par-4 eighth hole in Friday's second round. He said he had a simple sand shot from a greenside bunker but blasted poorly to about 20 feet from the hole and then three putted for another double bogey.

"I hit a few balls this morning," he said. "I'm going with my wife to watch a movie. There's nothing else I can do." He will leave today for Chicago for his last U.S. Open tuneup, the Western Open. Golden Chances for Some

When people say the Kemper Open has a lot of little known golfers, they are referring to the likes of Sonny Skinner, 29, of Sylvester, Ga., who yesterday shot one-under-par 70 in a quick round as the first player on the course. He barely made the cut after opening with twin 72s and now stands at one-over-par 214.

Ballesteros and defending champion Tom Byrum missed the cut and are down the road, but for unheralded players like Skinner that's of little concern. A tour rookie who has been to qualifying school seven times. he has a chance at his biggest check of the year. "I don't resent it when they say there's a weak field and there are no name players," he said. "It just makes me extremely determined. Hey, I think I'm somebody. I haven't proven it yet."

He is playing in only his 13th PGA Tour tournament. His best finish was last week in Atlanta, where he tied for 52nd, winning $2,255. His season total is $6,765. "It being a weak field does not reflect on this tournament, this location, or the layout of the golf course," he said. "It's the time frame. It's just because this tournament falls two weeks from the U.S. Open. They like this golf course and $1 million is a lot of money.

"I might not be the top guy on the list, but if I can go out there and improve like I did today.. . . I'm from a little bitty town in Georgia and it's a big adjustment to come out here."

The PGA Tour plays weekend rounds in twosomes to expedite play, but because he was an odd number, Skinner played with Avenel teaching director Steve Bosdosh, who is not officially in the tournament. Skinner made four birdies in his quick trip.

"It was fast," said Skinner. "I was the only player in the group grinding it out. He {Bosdosh} was really polite. When he'd hit it in the boonies and it looked like he'd take a large number, he'd pick it up and put it in his pocket." Thorpe Irons Out Problems

Jim Thorpe, former Falls Church resident, responded to the urgings of a big gallery with three birdies and three scrambling pars for a two-under-par 69 for 213. He switched to a new set of irons after opening with 73 and 71.

"I played absolutely beautifully with them," he said. "It's funny; when you get people behind you, it brings out the best in you."

He is not shy about saying that when he lived in Falls Church in the late '70s he was a golf hustler at Washington courses East Potomac and Langston, and in Baltimore. "That how I made it, hustling golf," said Thorpe, who now lives in Buffalo. "I believe it made me a better player. It's been a pretty good year."

He finished second in the Phoenix Open in late January for $97,200 and has won $147,263 this season. Now in his 13th season, he has $1,466,433 in career earnings . . .

Frederick native Donnie Hammond said he had "kind of a ho-hum round" of 72 and stands at 212. He said the four-foot par putt he missed on the first hole set the tone; the ball curled around the cup.

Officials estimated yesterday's crowd at 40,000, about the same as last year's Saturday showing.