Top drafters have staying power

Ozzie Newsome, left, has a knack for finding the right players for the Ravens' system. Bill Belichick excels at blending draft picks with veteran role players. AP Photo

As many teams found out over the past two decades, it's hard to win a championship through free agency. Teams have more cap room to keep their top free agents, so it's hard to get more than one or two starters in free agency. Typically, the teams that hit free agency the hardest are the teams that fail in the draft.

What do today's top draft evaluators have in common? They all have been drafting throughout this decade and still have jobs. Heading into Saturday's draft, here are the top draft evaluators in the league:

1. Ozzie Newsome, general manager, Baltimore Ravens
As a player, he was known as the Wizard of Oz, a Hall of Fame tight end who was hard to stop. As a drafter, he's a master of finding the right players. Newsome built one of the greatest defenses in NFL history, starting with middle linebacker Ray Lewis.

Normally, Newsome drafts players from major colleges, but, in typical Newsome fashion, he went against his profile to find the right quarterback for the Ravens. Last year, he took Joe Flacco out of Delaware. The Ravens won 11 games, and Flacco appears to be the quarterback who can challenge Ben Roethlisberger of the Steelers.

2. Bill Polian, general manager, Indianapolis Colts
Polian built the Buffalo Bills into a four-time Super Bowl team and the expansion Carolina Panthers into an NFC Championship Game participant. His work with the Colts has also been exceptional. Polian built the franchise around Peyton Manning. Because his salary cap is heavily loaded on offense, Polian is forced to build his defense through draft choices and undrafted free agents. He found the perfect coach to manage the system with the hiring of Tony Dungy and now is going with Dungy understudy Jim Caldwell.

3. Kevin Colbert, director of football operations, Pittsburgh Steelers
Colbert came from the Lions and fit perfectly in the Steelers' model of building through the draft. A native of Pittsburgh, Colbert always seems to find the right young player to replace outgoing starters. When the Steelers decided not to re-sign Plaxico Burress, he drafted Santonio Holmes. Now, Holmes is emerging as a star.

When Colbert needed youth to bolster a veteran linebacking corps, he drafted LaMarr Woodley and Lawrence Timmons. Obviously, the selection of Roethlisberger has put the Steelers back among the elite. Roethlisberger has been to the playoffs in four of his five years and has two Super Bowl rings.

4. Bill Belichick, coach, New England Patriots
Of all the coaches in the league, Belichick has the best eye for talent. He knows how to get the most out of players, and he's able to find players who fit his system. Over the past couple of years, New England's drafts have been criticized because several picks either didn't make the team or didn't emerge as starters. That criticism is unfair. There aren't many openings on most Patriots teams. Belichick loads his roster with veteran role players, so there aren't going to be many spots available when training camp begins. His rosters are usually set, and if he does make changes, he's going to lean toward veteran role players.

Belichick's strengths have been finding defensive and offensive linemen, and obviously, Tom Brady was the steal of the decade.

5. Andy Reid (coach) and Tom Heckert (general manager), Philadelphia Eagles
It's hard to argue against their accomplishments. Together, they have been to five NFC Championship Games and one trip to the Super Bowl. Reid and Heckert work for an owner, Jeff Lurie, who loves to study the draft, and the two have won him over with how they operate.

Few franchises work the draft better than the Eagles. They are one of the best in the league at gaining compensatory picks, which are awarded by the league for departed free agents. The Eagles are also one of the best teams in football in making trades for draft choices. Reid and Heckert are two of the most forward-thinking evaluators in the league because they are constantly looking for players to replace aging starters.

John Clayton, a recipient of the Pro Football Hall of Fame's McCann Award for distinguished reporting, is a senior writer for ESPN.com.