Washington Redskins quarterback Joe Theismann will not take his physical examination Sunday, as expected, but likely will wait at least until the weekend of July 26-27, Coach Joe Gibbs said yesterday.

Speculation on the reason for the delay centers on Theismann's $1.4 million insurance policy with Lloyd's of London that he took out to cover a career-ending injury. Sources have said that Theismann, who broke his right leg last season, needs the opinions of at least three doctors before he can file a claim for the money.

Theismann is seeking medical opinions and "collecting information on his injury," Gibbs said.

Although Gibbs declined to discuss Theismann's future, it is believed he will not pass the physical and will retire and join CBS-TV as a color commentator. Theismann could not be reached for comment yesterday.

After a wide-ranging -- and at times strained -- news conference four days before the opening of the Redskins' training camp at Dickinson College in Carlisle, Pa., Gibbs said he had not decided if he would ask his players to take drug tests at training camp.

According to a provision in NFL Commissioner Pete Rozelle's drug plan, which has been taken to arbitration by the NFL Players Association, teams now may administer drug tests to their players during the training camp physicals.

Gibbs said his players were not tested at the team's May minicamp, contrary to a statement made last week by middle linebacker Neal Olkewicz, the team's player representative.

Olkewicz said last night that "it's always been assumed" that a urine test taken by the players included an examination for drug use.

"Maybe that's not so," he said.

General Manager Bobby Beathard also appeared at the news conference and said the Redskins still have not signed any of their 11 draft choices, nor have they signed their five remaining free-agent veterans. NFL rules say players cannot practice unless they have signed.

"I don't think we've been in a position where we've been four days away from training camp and do not have a rookie signed," Beathard said.

Several players are close to an agreement, Beathard said, including veterans George Rogers, Clint Didier and Monte Coleman.

Gibbs said 10-year veteran tight end Rick Walker, who has knee and shoulder problems, is not expected to return to the team.

"Unless there is drastic improvement in the next couple weeks, he may have reached a point where he's not going to be able to play," Gibbs said.

Gibbs also announced that starting defensive end Charles Mann had arthroscopic knee surgery June 26 and is expected to report to camp on time, although the coaches "might take it easy on him" for a while.

Gibbs also said the team "will just have to wait and see" on the condition of veteran guard R.C. Thielemann, who is recovering from knee surgery.

But drug testing and Theismann's future were the hottest topics for Gibbs.

If the coach decides to test his players, it would be the first time the team has tested for drug use in Gibbs' six seasons as head coach, according to Redskins officials.

"I'm still making my decision on the issue," Gibbs said.

Gibbs said he is in favor of random drug testing, but declined to say specifically what he thought of Rozelle's plan, which calls for every NFL player to undergo two random drug tests a year.

"We have a drug program right now that does not work," Gibbs said. "The reason it doesn't work is that when you start talking about 'probable cause' the clause that allows teams to test athletes in the present drug plan , it doesn't work. Doctors aren't around the players . . . the coaches are. And in my six years as the coach here, I can say that I can't tell."

Gibbs added that Dr. Forest Tennant, the NFL's new drug adviser under Rozelle's plan, spoke to the Redskins for two hours during minicamp. Gibbs said he also expects to continue discussing the issue with the players when rookies and selected veterans report to training camp Sunday.

Theismann had been expected to report for his physical Sunday, but Gibbs said that's been changed. Now the quarterback is scheduled to report with the other veterans the next week, and that is subject to change.

The examination of X-rays and team doctors' evaluations of Theismann may take place at Redskin Park, not in Carlisle, Gibbs said. And there seems to be no certainty about a date.

"We're continuing to step through it slowly," Gibbs said. "We'll give him absolutely as much time as we can."

One Redskins official recently called the Theismann situation "completely muddled." Apparently, the Redskins are walking a fine line between allowing Theismann to continue his rehabilitation and telling him he cannot return for the 1986 season.

For the first time yesterday, Gibbs said that "most doctors" would have predicted an 18-month recovery period for Theismann, not six months as was previously mentioned. Theismann was injured Nov. 18, 1985.

Gibbs, who snapped at a reporter when pressed about competition between Jay Schroeder, the apparent No. 1 quarterback, and Theismann ("I've answered that 1,000 times," he said), later said he did not want to speculate about Theismann.

"When there might be an obvious answer coming, why should we sit and guess about the options?" he said.

The Redskins announced they have signed running back Wesley Williams, the most valuable player in this past spring's Italian Football League Super Bowl. Williams, who is from Angelo State (where former Redskin Alvin Garrett played), becomes the 117th player on the Redskins' roster.