Harold Soloman of Silver Spring, Md., worn out by his victory Friday over top-seeded defending champion Jimmy Connors, was beaten today by John Alexander, 6-4, 6-1, in the semisfinals of the $125,000 Volvo International tennis tournament.

Alexander, who had two close losses to Solomon the previous three weeks, will play Manuel Orantes for the $20,000 top prize Sunday.

Orantes, the 1975 U.S. Open champion who resumed competition three weeks ago following surgery to relieve a pinched nerve in his left arm, ousted Eddie Dibbs, 6-3, 7-6.

Dibbs sportingly gave Orantes the benefit of doubt on two calls in the decisive tie breaker.

"Orantes is one of the most honest guys on the court. He's given me calls in the past and I wasn't going to hook him there," Dibbs said.

Alexander served four aces on the slow red clay of the Mt. Cranmore Tennis Stadium and generally was sharper than Solomon, who had beaten him in recent tournaments at Cincinnati and Washington. Alexander broke serve to win the first set and rolled on from there.

Solomon said he was drained by his 1-6, 6-4, 6-1, win over Connors in the quarter finals, his first victory over the top-ranked American since 1972.

"But that's no excuse. I had a lot of chances to win but I started serving very poorly for some reason and that was it," Solomon said.

Orantes kept Dibbs off balance by mixing soft balls and drop shots with deep groundstrokes, winning the first set in 32 minutes and taking a 5-2 lead in the second. But Dibbs stormed back to lead, 6-5, and force the tie breaker.

Dibbs was ahead, 2-1, when he asked a point to be replayed after an Orantes lob was called long. Orantes won the replayed point with a backhand passing shot and eventually took the match on an ace that was first called a fault, then changed when Dibbs asked the linesman to look at the mark on the clay.