Posey drove the lane after the Sacramento Kings forced David West to pass the ball back out to the perimeter, then found Songaila under the basket for a tough layup with defenders crowding around him.
The basket with 12 seconds to go gave the Hornets a slim lead they would not relinquish in a 96-94 victory on Tuesday night.
"It was one of those plays where you get it and you make the shot and then you're like, 'What just happened? How did I make that? Can I do it again? I don't know,' " said Songaila, who figured he's had one or two game-winning shots in his six-year NBA career. "Any time you get the ball under the basket you've just got to go up as strong as you can and hope you get fouled or get the layup."
West led New Orleans with 24 points and 12 rebounds. Chris Paul, in his second game back from a sprained left ankle, had 15 points and 12 assists. Emeka Okafor added 17 points and 12 rebounds for New Orleans, and Songaila led the reserves with what turned out to be a crucial 11-point effort.
Sacramento's Andres Nocioni had a chance to tie it when he rebounded Tyreke Evans' miss and was fouled with just over a second left. He missed his first free throw, however, then was forced to miss the second in hopes of a putback that never had a chance because of a Kings lane violation.
"I knew he was going to miss it," said Songaila, who fouled out on the play that put Nocioni on the line. "I played with Noc in Chicago so I knew he wasn't a good free throw shooter. I told one of my teammates he was going to give us one [miss] and it turned out he gave us two. Obviously, it wasn't the play I was going for but it turned out lucky."
Evans led the Kings with 25 points. His free throws, followed by his soaring fast-break scoop off the glass, gave the Kings a 92-91 lead with 1:22 left.
"It hurts to play as well as we did and not come away with the win," Kings coach Paul Westphal said. "When we start learning how to win these games, it's going to be fun to watch."
West hit a short jumper off the glass to put New Orleans back up 93-92. After Evans' miss, West was fouled inside but made only one of two free throws, allowing Evans to tie it at 94 with a driving layup with 33 seconds left.
That set up Songaila's winner.
"As the defense rotated, I was able to penetrate," said Posey, who also hit a key 3-pointer late in the fourth quarter. "Once the bigs came, I saw Darius right there."
The Kings led 76-69 early in the fourth quarter, but reserve Marcus Thornton provided a sudden scoring surge that kept the Hornets within striking distance. He hit a 3 from the wing, then stole the ball for a fast-break layup to pull New Orleans to 78-77.
"We knew we would need those guys to win games like this," West said. "Darius came in and played big and Marcus did the same thing."
Jason Thompson scored 20 and had nine rebounds for Sacramento, hitting an array of tough inside shots and short floaters, but he fouled out on a charging call with 3:25 left and the Kings trailing 88-85.
The Kings dominated the inside, where they outscored New Orleans 56-34. Sacramento also ran the floor better, finishing with a 22-8 advantage in fast-break points.
Sacramento also shot slightly better, 50.6 percent to 50 percent.
"We are improving," Hawes said. "Guys have grown individually and meshed as a unit and I think it's only going to continue."
The Hornets pulled it out by hitting eight 3-pointers and outscoring the Kings 14-9 at the foul line, where the Kings missed 10 free throws.
Peja Stojakovic was 4 of 5 from 3-point range and had 14 points.
Stojakovic hit three 3s in the first half, one of them giving the Hornets their largest lead at 29-17 late in the first quarter.
Evans cut the Kings' deficit to 10 with a layup in the final seconds of the period, but paid for it. He was bumped by Okafor, though no foul was called, and crashed hard to the floor. He went to the locker room for the first five minutes of the second quarter, but returned to help the Kings pull to 35-34 on a driving layup as he was fouled.
The score was tied at 48 at halftime.
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