Both sides in the baseball negotiations today criticized proposed solutions offered Thursday by Commissioner Peter Ueberroth, but they nonetheless scheduled a negotiating session for Saturday in an effort to avert a players strike set for Tuesday.

The sides have not met since Wednesday.

Ueberroth presented his proposal, portions of which he outlined the day before in a news conference, in writing today to Lee MacPhail, chief negotiator for the owners as head of the Player Relations Committee, and Donald Fehr, head of the Major League Players Association. Publicly, they expressed contrasting opinions but the bottom line was this: neither much liked the plan.

"I have to sharply disagree with a couple of things," MacPhail said. "First, he (Ueberroth) said the owners should not look to the players to solve their financial problems. We're not doing that. All we're asking is that the players work with us to set up some kind of system to control costs and equitably share the costs between us.

"The other suggestion about putting in escrow the $45 million (disputed for the players' pension fund) is slightly bizarre. That money belongs to the clubs. It doesn't belong to the players, except for any money they can negotiate with us to put in the pension fund. That money hasn't been received yet, but it is already committed to pay for operating costs, which, for the most part, are players' salaries."

Fehr, who has always maintained that the union considers the commissioner part of the owners' group, said, "Most of the ideas appear to be, in one fashion or another, a rehash of management proposals made this year or in past years."

The PRC executive committee was to meet here tonight to go over the Ueberroth proposal before sitting down with the players Saturday. Ueberroth also asked the players to go on playing past Tuesday's strike deadline, but no commitment has been made by Fehr to do that.

The players are seeking about a $45 million (from $15.5 million to $60 million) increase in the owners' contribution to the players' pension fund. The players have traditionally, but not contractually, received one-third of the network television contract and that is how they arrived at the $45 million figure, since the owners signed a six-year $1.1 billion network deal before the 1984 season.

Under Ueberroth's plan, the players would continue playing and finish the season while the sides negotiate how to split the money. The $45 million difference would be put in an escrow account.

"They could set a date, any date, say Aug. 10, then set a 45-day period, in which to discuss the item," Ueberroth said. "But there needs to be a penalty. So $1 million a day would be taken out for each day they bargain. They would be bargaining for a lesser amount each day." The money withdrawn from the escrow account would go to amateur baseball or another charity.

Another point in his proposal calls for the owners to drop discussion of a salary cap or negative changes in the free-agency system.

Although Ueberroth called his proposal "the plain and simple solution," it gets complicated. Under it, the owners also would increase their pension contribution retroactively for 1984 and begin negotiating a pension contribution increase for the next five years "from a low of 50 percent, above and beyond the $15.5 million, up to 100 percent," he said.

In return, the owners get a break on the thorny salary arbitration issue. Current major leaguers would, in effect, be "grandfathered," said Ueberroth, and remain in the present system, in which they are eligible for arbitration after two years. Future players would be eligible after three years and would be limited to a 100 percent increase from their previous salary in any award given by an arbitrator. Ueberroth said there would be a "superstar clause" for players who fulfill certain criteria, and there would be no limit on the increase allowed on those players.

"I'm an optimist and always have been," MacPhail said. "But it's difficult to say you are an optimist because we have so little time left and haven't closed the gap."

Denying that tempers were rising, Fehr had a similar sentiment.

"You can have a duel civilly," he said, "but people still get killed."