Two strange things happened in Dennis Conner's America's Cup camp this week.

First, he and his yacht Liberty were beaten twice straight by old nemesis Courageous in their first meeting in final trials to select a cup defender.

Second, and perhaps more significantly, a crewman from Conner's burgeoning support group was heard to comment the following day, "It was good for Dennis. He's cocky and he needs to get knocked down."

Such criticism in the highly stratified Conner camp is rare. Never was heard a discouraging word in Conner's landslide march to victory in 1980. Now come potshots from his own people.

Conner's rigid philosophy in cup racing has been to leave nothing to chance. This businesslike approach put him in stark contrast with his brash predecessor, Ted Turner, the so-called Captain Outrageous whose keys to fortune were inspiration, wit and charm. Some say Conner took the fun out of the cup.

Now come some fast-sailing youngsters in Turner's old boat and some fun-loving Australians with a wacky new hull design in foreign challenger Australia II, and suddenly the crowd is cheering and Conner is on the ropes.

Or is he?

The Dennis Conner who is competing for the right to defend the cup this time is a different fellow from the last go-around. He's three years older, a good deal beamier around the middle, and, for the first time in recent cup competition, he's had to absorb a few blows.

Two years ago one of his goals was to develop a faster boat than Freedom, his '80 champion. He and his syndicate built three boats, expended massive energy and financial resources, and he is the first to admit they failed.

"We didn't find a breakthrough," Conner said today. His colleagues said Liberty is probably no faster than Freedom would have been, had they simply dedicated themselves to updating her.

While they diddled with new boats, his top crewmen agreed today, the Conner crowd had to put some of the important precepts of their 1980 campaign on a back burner. "Maybe we could have spent our time more productively working on improving our sails or crew work," said tactician Tom Whidden.

Gary Jobson, Defender's tactician, said Conner will go to great lengths to give himself a tiny edge in boat speed. This year, trials so far have shown he did not succeed.

Yet he is odds-on favorite to win the right to defend.

What, then, will his advantages be?

Conner's secret plan to speed up the boat were unearthed by the Defender crew and were later rendered impractical by the race committee. A decision to upgrade Liberty's meteorological staff lost its impact because of the plan's failure.

So it's even-up. All Conner has to bank on is his experience, his heralded managerial skill over the biggest support staff of any contender, a sharply competitive vessel, his fighting instincts and his status with the selection committee as defending champion.

According to Liberty sail-trimmer John Marshall, who has been with Conner through both campaigns, his competitors believed "that Dennis would cave under the pressure. They wondered how a habitual winner would perform under that kind of stress."

But that, said Marshall, "is a great and unrecognized strength of Dennis'. He's poised, confident and he will take the advantage when he gets it."

Whidden and Marshall, who compares 12-meter racing to boxing, said they believe Conner has not yet been stung by his opponents. A few jabs have landed, particularly by Courageous, they say, but that only serves as a challenge to their skipper.

The difference between 1980 and 1983, Conner says, is that the last campaign was a walkaway, both over American contenders and the foreign challenger, Australia I.

The strength of the '83 American campaign, Connor said, is that the contenders are evenly matched enough to push each other to sailing perfection before one is chosen for the showdown with Australia II, beginning Sept. 13.

Conner and his crew expect the defense trials to go down to the bitter end, with a selection not likely until close to the final day, Sept. 8.

It's a far cry from 1980, when Conner waltzed to the cup.

Today's races were postponed because of poor visibility and lack of winds on Rhode Island Sound. The postponement delayed by at least a day the possible clinching of berths in the challenger finals by Australia II and Victory '83. Both boats need one victory or a loss by the Italian entry Azzurra to become the last two survivors from an original field of seven foreign boats.