Tim Duncan lunges to bat the ball away from Nuggets forward Ryan Bowen.

This week Fred "Mad Dog" Carter deals with the top five defenses in the NBA. If you look at points allowed, these fab five are the tops in the league by a significant margin. Our photo for each team will be of someone on the defense Fred refers to.

By the way, Fred visits the ESPN.com audio chat room each Thursday at 4 p.m. ET, so check in with him and NBA editor Eric Karabell each week. If you have comments about Mad Dog's Top Five or the weekly chat or anything NBA, tell us by clicking here.

Here's this week's Mad Dog's Top Five.

MAD DOG'S TOP 5 NBA DEFENSES
Rasheed Wallace	Portland	Allowing 88.6 ppg; .412 FG % "This is a big team, an athletic team with great size, from Rasheed Wallace to Brian Grant to Arvydas Sabonis. And when Scottie Pippen came to town, it affected the intensity and overall mindset of the team. If he goes all out, it becomes infectious. Other players see Pippen playing defense and they don't want to be the guy that the coaches point at and say they're not playing the same kind of defense. So with the whole team, the mindset changes."
David Robinson	San Antonio	Allowing 89.2 ppg, .414 FG % "The Spurs are a big shotblocking team. They discourage teams from going into the paint and that really makes a difference. When David Robinson and Tim Duncan play badminton with your shot, you stop testing them. And with these guys staying back near the basket it allows everyone else to play closer defense and take some chances. You force other teams to create where the traffic is high."
Kurt Thomas	New York	Allowing 90.2 ppg, .404 FG % "Ever since the days of Pat Riley, this club has always played great defense. The mentality is just set. And it's not just Marcus Camby and Patrick Ewing and the shotblockers, it's everyone. These guys know how to play defense. Jeff Van Gundy does a great job preparing them on what to do. It's not shotblocking or quickness and speed, it's team play and getting weakside help and knowing what they are going to do and defensive rebounding. They do it all."
Bryon Russell	Utah	Allowing 90.4 ppg, .442 FG % "This is the old men and the sea, and I don't mean Ernest Hemingway. Karl Malone, John Stockton, Jeff Hornacek as well as Bryon Russell and Greg Ostertag -- they know what to do. And give Jerry Sloan a ton of credit here. It's not a quick team, not a shotblocking team -- just a great team defense concept. They read and understand what the offense is going to do. Stockton and Hornacek are as good defensively as any guard tandem."
Shaquille O'Neal	Lakers	Allowing 90.7 ppg, .407 FG % "With L.A. everyone talks about the triangle offense and is amazed with how well it's working, but they forget that it's defense, too. Chicago played outstanding defense to win those titles. That's what this team is really about. Shaq didn't run back on defense last year, but now I see him doing it. I see guys rotating and helping out. The game against Denver the other night, it's always five players in concert. When that happens on offense, you get baskets. When you do it on defense, you get stops."