Hill and Nash, who was 3 of 13 from the field, missed shots in the final minute. Brook Lopez had a chance to extend the lead to three points with 9.3 seconds to go when he was fouled, but he missed the second of two free throws.
Phoenix called a timeout and set up Frye.
Williams seemed to will the overtime, assisting on the final five Nets baskets in regulation, including 3-pointers by Morrow with 22 and 10 seconds to play, the last one cutting the Suns' lead to 94-93.
"It was good. The fans were great tonight," Williams said. "We tried to get them a win. We just came up a little short."
Phoenix seemed to be in control when Frye scored on a dunk off an inbound play with 8.5 seconds to go and the Nets out of time.
Williams got the inbound pass, dribbled up the court and found Morrow on the left wing for a 3-point attempt. Nash tried to block the shot and fouled the Nets guard with 2.5 seconds to go. The 90 percent free throw shooter hit nothing but net in tying the game.
"That's ridiculous," Suns coach Alvin Gentry said. "That's the worst basketball game I've seen down the stretch. That was horrible. We were lucky as anything to win the game."
Phoenix called a timeout to set up a game-winning shot, but they were called for a five-second turnover, giving New Jersey the last shot. Sasha Vujacic could not beat the final buzzer with his off-balance attempt.
The Nets did their best to make Williams' first game at the Prudential Center memorable. The first 10,000 fans received T-shirts with No. 8 on the front and his name on the back.
And when the lineups were introduced, Williams was saved for last and got the royal welcome from announcer Gary Sussman, with many in the crowd of 15,836 giving him a loud standing ovation, although there might have been some piped in noise to help.
Notes: Former Giants and Fox football analyst Michael Strahan was sitting courtside. Beyonce and rapper Jay-Z, a Nets' minority owner, sat next to the New Jersey bench. ... Humphries brought the crowd to its feet late in the first half by blocking a dunk attempt by Robin Lopez. ... Vujacic seemed to wake the Nets up on the final play of the first quarter, hitting a halfcourt shot at the buzzer.
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