The first clue was that Ken Moffett, the federal mediator, ran only seven miles Thursday morning. Usually, it's 10, but not on days when he expects marathon negotiations.

At 2:16 Friday morning, as a strike by the Major League Players Association neared, Moffett came down to the press room and announced that there soon would be an announcement. It was the most hopeful thing he had said all week.

Three hours later, he returned with Marvin Miller, the executive director of the players' association; Ray Grebey, the owners' chief negotiator, and Commissioner Bowie Kuhn, the only one who did not look tired.

They had gone the distance. They had reached a new basic agreement, and averted the third player strike in baseball history.

"We couldn't have done it without the Goldfish and the oatmeal cookies," Moffett said.

Grebey said the settlement, which stunned just about everyone, "had something in it for everyone."

That includes the possibility of a strike next season and a continuation of the tactical squabbling that characterized the talks up until the final handshakes had been recorded by photographers.

Although the negotiators were able to reach agreement for four years on many issues, including pension benefits and minimum salary, the familiar free-agent compensation question was tabled for a year and put to a one-year joint study committee.

The players' association had proposed May 15 putting the issue to a two-year study committee but the owners said no, demanding it be resolved now.

Asked what he thought he had given up, Miller said, "I'm still looking for it."

"We postponed what they said could not be postponed" said Richard Moss, the special counsel to the players' association.

But they could not postpone the morning-after bitterness when Grebey issued a press release on the agreement, which Miller said "distorted the facts."

The facts are these: The agreement calls for establishing a four-member committee, consisting of two players and two club operating officials, which will present a report by January 1, 1981. If the committee makes no satisfactory proposal, the parties will negotiate 30 days. If there is no consensus by Feb. 15 according to the agreement, "the clubs may unilaterally adopt and put into effect as part of the basic agreement the proposal on this matter" that had been on the table. That would require the team signing a premium free agent to give a roster player in return "or a variation not less favorable to the players' association."

However, the players' association, in turn, has the right to strike on this issue, before June 1, 1981 (the players have the right to waive that strike and to strike one year later).

Miller, head of the association since 1966, has planned to retire and become a beach bum. If there is a strike in April, he said, "I'll be there."

Grebey's press release stated that in 1981, "The club's proposal for compensation becomes a part of the basic agreement and it cannot be removed without agreement of the two sides."

The Associated Press carried a story saying that the owners' proposal for compensation based on a formula of freezing 15 players in exchange for a premium free-agent would be in effect next season.

Miller said that the story made him "furious because it was so inaccurate. He said he called Grebey before having read the press release and that Grebey mused, "What can you do about these people?" (the reporters).

"I did not realize that it wasn't the (reporters') fault at all," Miller said.

"The press release," he added, "is so horribly inaccurate that I don't know where to begin. I can only ascribe it to fatigue. They've turned purple into green and night into day. It is certainly not my intent to start a new relationship with the owners by criticizing, but I don't think any service can be done by distorting the facts."

Grebey could not be reached for comment.

The rest of the new four-year agreement, which replaces the one that expired Dec. 31, is less controversial and includes provisions which:

Increased the owners' contribution to the players' pension fund from $8.3 million to $15.5 million, as the players proposed this week. (Miller said, "We've always maintained that we're entitled to approximately one-third of the money from the television package, over four years, and this is $62 million vs. the $185 million" baseball receives from the new network contract.)

Raised the minimum major league salary from $21,000 to $30,000. (It will escalate to $35,000 by 1984).

Fixed the minimum salary for players with split contracts (between the major and minor leagues) at $14,000. (It will escalate to $16,000 by 1984.

Doubled the benefits, including those for disabled players, to $20,000.

Enlarged eligibility for salary arbitration.

Thursday morning, it seemed hardly likely that they could agree on this much. In fact, none of those issues, Miller said, was resolved before Thursday night.

Perhaps it was the unexpected presence in the hotel of John Gaherin, the owners' negotiator in 1976, that produced the movement. But there were other factors.

Early Thursday, Miller said it would "take a small miracle" to avoid a strike Friday.

When asked today what that miracle was, Miller said, "I don't think it occurred in my presence. There were those owners from the beginning who felt there would be no strike and suddenly they looked up and said, "there it is.' The small miracle was in that flash of understanding that the owners got."

Moss said the agreement could have been reached "over lunch last summer," except that several owners wanted to test the players to see if they would stick together. They weren't convinced until the very end. As long as it's that way, we are always going to have crisis negotiations in baseball and it's totally unnecessary."

In addition to the hardliners, some of whom were on the players relations committee, there was a splinter group, led by Orioles owner Edward Bennett Williams and Astros owner John McMullen, working for peace.

Williams and McMullen began to exert their influence, talking with the commissioner and other owners, trying to avoid a strike.

And, finally their message began (to Rona counsel its Grebey), Dan Fehr (the union's legal counsel) and Moffett met privately Wednesday afternoon at the Barclay Hotel, avoiding waiting reporters by taking a freight elevator and speaking through the hotel bar. Miller again floated the idea of a study committee but almost everyone still was treading water.

They met again at about 3 p.m. Thursday while the official meetings were in recess. This time Grebey suggested a study committee, but only after Miller left.

Two hours later at the official meeting, Grebey discussed a joint committee seriously and suddenly settlement was possible. "For this kind of change of heart to take place in a snap of the fingers at the 11th hour, someone had to cave in," one source said. "It was the ultimate in brinkmanship. Who's going to blink?"

Negotiations resumed at 10 p.m. while Moss and Fehr played gin rummy and poker. Miller and Grebey went one on one, calling each other's bluff, ironing out details of the contract.

Player representatives kept calling to find out if they should board planes.

The negotiators kept working. The last issue discussed was the players' right to strike in April 1981, should the owners implement their proposal for compensation.

The owners wanted to set a strike deadline of no later than April 1. They settled on June 1. The message, sources said, seemed clear: The owners did not want a strike during the middle of the season, while they were most vulnerable at the gate, this year or next.

Was this a defeat for the players' association? "When someone asks for something you consider intolerable and you get them to defer it, how can it be a defeat?" Miller asked.

Miller said it will take three weeks to a month to get the contract ratified by the players. He said he expects no trouble.

The players can hope that in the next year, the issue will cool off, the owners will cool off, or that the owners will not be prepared to go the mat again.

The owners, if they still are determined to institute a system of compensation, can hope that Miller will retire and they will have someone easier to negotiate with.

At 4:30 a.m., when it was time to start calling the owners to sell them on the contract, the caller said to one of the owners, "Howsam likes it." Cincinnati owner Bob Howsam was one of the hardest of the hard-liners.

All can hope that, in the meantime, the joint study committee will resolve the problem satisfactorily to everyone, and that Mighty Casey won't have to walk out.