"Yo Picasso" ("I Picasso"), a confident, ferocious self-portrait painted by the Spanish master in 1901 when he was 19 years old, sold yesterday for $5.3 million in the Manhattan salesrooms of Sotheby Parke Bernet.

The large crowd in the auction room broke into applause as soon as the Picasso appeared on the stage. Three minutes and eight seconds later, after spirited bidding, the Picasso, painted during his second trip to Paris, became the most expensive 20th-century picture ever sold and the fourth most expensive picture ever sold at auction. It was purchased by an American private collector who left the auction room immediately and refused to state his name.

The black-eyed, black-haired Picasso wears a fiery orange cravat and stares into the mirror as if to dare the viewer to meet his piercing glance. The slashing brushstrokes reinforce the painting's crackling energy. Only pictures by Rubens ($5.1 million), Velazquez ($5.54 million) and Turner ($6.4 million) have ever gone for more. Because Manhattan's auctioneers now charge buyers a 10-percent commission, the picture actually cost $5,830,000.

The Picasso sale was the high point of an evening auction in which the 93 lots offered brought a total of $20 million. "These seem to be the best times," said David Nash, Sotheby senior vice president and director of fine art sales. Only 19 lots remained unsold, though bidding for an additional 17 failed to reach the low presale estimates set by the auctioneers.

One other canvas, a sugary and lushly painted scene of two girls reading, painted by Pierre-Auguste Renoir in 1890, also did exceptionally well, going to a European private collector for $2 million, a record for Renoir. One of the girls is Julie Manet, the daughter of painter Berthe Morisot. Degas' portrait of Julie's father, Eugene Manet, the brother of the painter Edouard , sold Tuesday night at Christie's Sotheby's chief competitor, for $2.2 million.

Some $50 million worth of art has already been sold at auction in New York this week.

Four other artists' records -- Alfred Sisley ($450,000), Rene Magritte ($380,000), Pierre Bonnard ($310,000) and Aristide ($220,000) were also set last night.

Though the first few sales of the week, those organized by Christie's, were far less successful, last night's -- billed by Sotheby's as the "the most important assemblage of Impressionist and Modern works from various owners to be offered in recent years" -- was not a disappointment.

"Yo Picasso" was one of the most popular self-portraits seen in the enormous Picasso retrospective last summer at the Museum of Modern Art. He had not yet entered his Blue Period, but could already paint with extraordinary power. The painting had been sold six years ago by Christie's for $650,000.

Eight pictures offered last night -- works by Renoir, Degas, Soutine, Rouault, as well as four Picassos -- came from New York's Guggenheim Museum. All eight were once owned by the late Justin K. Thannhauser, the son of a Munich dealer, who left them to the Guggenheim when he died five years ago. "Mr. Thannhauser, in his will, provided that we should have the freedom to round out his collection and to sell works that, in our judgment, and that of the Thannhauser Foundation, were not essential -- providing only that all proceeds are used to buy works of the same period for installation in our Thannhauser wing," said Thomas Messer, the Guggenheim's director. "We've already made one very important purchase with the anticipated returns of the sale. We bought a Cubist Braque of 1919 called 'Le Buffet.' It's a capital work. It is already on view." The Degas did not sell last night. The other seven earned the museum $870,000.

A number of other paintings -- works by Renoir, Sisley and Monet -- were sold by Boston's Museum of Fine Arts. The $1.135 million that they fetched will help pay for the famous Gilbert Stuart portraits of George and Martha Washington, which Boston's Museum now owns jointly with Washington's National Portrait Gallery.

The major reason for the success of last night's auction, and the relative failure of those organized earlier, appears to be the high reserve prices set by Sotheby's competitor, Christie's. Auctioneers these days estimate the prices that the works for sale will bring. Twenty-four works sold last night for figures above presale estimates, 36 for prices below what was expected and the rest were on the mark.

Jack Nicholson, singer Paul Simon and director Mike Nichols were present in the standing-room-only crowd.