"Together", The Times opined, "the sales signaled a new inclusivity in the art world, driven by a generational shift toward artists who have been out of the mainstream, and driven by stratospheric prices for more established names".
It became the most celebrated of the artist's series of pool paintings, begun after he moved to California from the relative gloom of Bradford.
Working 18-hour days for a solid two weeks before the show, Hockney has recalled he "literally finished the painting the night before it had to be sent off to the exhibition".
The picture dates back to the year that their great love affair ended, and the swimmer could be Peter's new lover.
Alex Rotter, co-chairman of post-war and contemporary art at Christie's in NY, told the Associated Press in September that it is "the holy grail" of Hockney's work.
The buyer's premium took the final price to $90,312,500, the auction house announced.
The painting was bought by a client of Marc Porter, chairman of Christie's Americas. One, fully clothed, stands at the edge of a swimming pool gazing down at another, who is submerged. The hilly landscape behind them was inspired by the South of France.
Upon his return to London, Hockney worked 18 hours a day for two weeks to complete the new painting before it was scheduled to be sent to NY.
"He is someone who has an extraordinary eye", said Pylkkanen, who has known Lewis for years.
The painting led Christie's postwar and contemporary evening sale that totaled $357.2 million, within the estimated range.
This week's sales, which kicked off November 11 and included Impressionist, modern, postwar and contemporary art, have generated $1.96 billion, eclipsing the $1.8 billion estimate.