Deron Williams of the Brooklyn Nets lays up a basket...

Deron Williams of the Brooklyn Nets lays up a basket against the Golden State Warriors at Barclays Center in Brooklyn. (Dec. 7, 2012) Credit: Jim McIsaac

Avery Johnson has his own meticulous way of tracking the Nets' defense, using a rating to break down information into various categories.

Even if he graded the way things shook out in Friday's 109-102 loss to the Warriors on a steep curve, the Nets probably still would have flunked. It was as if they forgot the answers to a test they'd already passed more than once this season. Their defense was that horrendous.

"One of the lowest [ratings] we've had all year," Johnson said after practice at Barclays Center on Saturday. "Our rating works, our defense works. But we need energy. We've got to guard penetration. We probably had our worst defensive rating in transition. We had no defensive presence whatsoever."

Johnson forced the Nets to relive some of those ugly moments Saturday, showing them video of a defensive debacle in which they were pushed around by the Warriors. It had to be like looking at a horror flick well after midnight.

The Nets (11-7) allowed 50 points in the paint, got outrebounded 47-44 and were outscored 54-39 in the second half. They never matched the Warriors' energy, something they know can't happen Sunday night if they're going to beat the Bucks (9-9) and end their three-game slide.

"The film really was bad," Deron Williams said. "You go back and watch that game and watch that energy level and see us -- every one of us, from me down to the last guy. We looked at the benches. Their bench cheering versus our bench when something happens. It was just a bad vibe last game. We have to change that and we know that."

Brook Lopez's absence hasn't helped, and although he did a little work in practice Saturday, it's uncertain when the 7-footer will return to action.

Johnson said Lopez, who has a sprained ligament in his right foot, wasn't involved in any contact and didn't technically practice. Lopez did a little light running and agility work and put up a few shots. But Johnson wants to see him practice and recover without any incidents before he even thinks about putting him in a game.

Lopez is no savior, anyway. "When Brook has been here, we've still gotten scored on some in the paint," Johnson said. "But he makes you think twice with the way he's blocking shots, and that's what we need from the rest of our guys. We need to take some more charges if we are not going to block shots.

"There are more charge opportunities and our charge attempts are down. I would rather us get called for more blocking fouls attempting a charge more than we are right now."

In other words, buy into those defensive philosophies that had been working so well, not the bad habits that have led to an average of 109.3 points yielded in the Nets' last three games.

"We won five in a row," Williams said. "We just lost three in a row. We need to get back to winning. We need to get back to playing defense. We have to do what makes us successful. We haven't been doing that the last three games. We saw it in the film. We need to change it. It's on us to change it."

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