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When New Orleans Saints quarterback Drew Brees hoisted the Lombardi Trophy following Super Bowl XLIV, three of his starting offensive linemen and his No. 1 receiver were guys who had entered the NFL via the fourth round or later.

So even in an era in which anybody with a laptop and Internet access can — and seemingly does — produce a detailed first-round mock draft, no modern-day draft "guru" had or celebrated the Saints taking right guard Jahri Evans of Division II Bloomsburg University 108th overall in 2006 … or Hofstra receiver Marques Colston with a supplemental compensatory seventh-rounder in 2006 … or left tackle Jermon Bushrod 125th overall in 2007 … or left guard Carl Nicks in the fifth round in 2008.

When the excitement of Thursday's first round passes and Friday brings a close to the second and third rounds, even the most educated and caffeinated NFL fan probably won't know how to react to what his favorite team does on Day 3.

Rounds 4-7 will unfold rapidly in front of a bleary-eyed, sun-deprived nation that's still digesting what happened 48 hours earlier. But that Day 3 action is an important part of building a franchise. It's the day teams strive to improve their special teams, create reliable depth throughout the roster and prove that their scouting department has a nose for sniffing out future Pro Bowl gems such as a Brandon Marshall (fourth round, 2006), a Robert Mathis (fifth round, 2003), an Antonio Brown (sixth round, 2010), a Cortland Finnegan (seventh round, 2006) or a Wes Welker (undrafted, 2004).

"We have specific goals for each round," said Rick Spielman, Vikings general manager. "I think the Day 3 guys, if you're lucky enough to get starters, you're doing a heck of a job … You go back to what kind of football player are they, and can this guy play better than where he was drafted?"

Since Spielman assumed control of the Vikings' draft in 2007, he's plucked six players from Rounds 4-7 who are current starters or key contributors. Defensive end Brian Robison (fourth round, 2007), nose tackle Letroy Guion (fifth round, 2008), center John Sullivan (sixth round, 2008) and safety Jamarca Sanford (seventh round, 2009) are the starters. Lineman Everson Griffen (fourth round, 2010) is a key defensive player and Blair Walsh (sixth round, 2012) is the league's reigning All-Pro kicker.

"Those [Day 3] guys can be special teams players and contribute if they have to play," Spielman said. "The main thing for me is you're adding depth to your roster where you have to make sure that you're comfortable playing those guys if they have to play. But they're still helping you to win ballgames."

From 2003-2012, the New England Patriots acquired a league-high eight "Day 3" players and rookie free agents who went on to become Pro Bowl players. San Diego and Dallas tied for second with seven apiece. The Cowboys got quarterback Tony Romo (2003) and receiver Miles Austin (2006) as rookie free agents. The Chargers got Antonio Gates and Welker as rookie free agents in 2003 and 2004, respectively.

The Bears led NFC North teams with four. The Vikings and Packers were second with three, while the Lions had one.

The only teams that haven't uncovered at least one future Pro Bowl player via this route are St. Louis and Washington.

Using the past 10 drafts, one could assemble quite an All-Star team using just "Day 3" players and undrafted rookies who have played in at least one Pro Bowl. Here's one possible All-Star squad (teams listed are the ones that selected the player):

WRs: Brandon Marshall (Broncos, fourth, 2006); Wes Welker (Chargers, undrafted, 2004). Left out: Victor Cruz (Giants, undrafted, 2010).

LT: Jermon Bushrod (Saints, fourth, 2007).

LG: Carl Nicks (Saints, fifth, 2008). A two-time All-Pro.

C: Dan Koppen (Patriots, fifth, 2003). Left out: Scott Wells (Packers, seventh, 2004).

RG: Jahri Evans (Saints, fourth, 2006). Four-time All-Pro.

RT: David Diehl (Giants, fifth, 2003).

TE: Antonio Gates (Chargers, undrafted, 2003).

QB: Tony Romo (Cowboys, undrafted, 2003).

RB: Arian Foster (Texans, undrafted, 2009). Left out: Michael Turner (Chargers, fifth, 2004), Willie Parker (Steelers, undrafted, 2004).

FB: Le'Ron McClain (Ravens, fourth, 2007). Left out: John Kuhn (Steelers, undrafted, 2005); Jerome Felton (Lions, fifth, 2008).

DEs: Jared Allen (Chiefs, fourth, 2004); Elvis Dumervil (Broncos, fourth, 2006).

DT: Kyle Williams (Bills, fifth, 2006). Left out: Henry Melton (Bears, fourth, 2009).

NT: Jay Ratliff (Cowboys, seventh, 2005).

LBs: Cato June (Colts, sixth, 2003); Shaun Phillips (Chargers, fourth, 2004); Robert Mathis (Colts, fifth, 2003).

CBs: Cortland Finnegan (Titans, seventh, 2006); Asante Samuel (Patriots, fourth, 2003). Left out: Nathan Vasher (Bears, fourth, 2004).

SS: Antoine Bethea (Colts, sixth, 2006).

FS: Dashon Goldson (49ers, fourth, 2007).

KR: Joshua Cribbs (Browns, undrafted, 2005).

P: Andy Lee (49ers, sixth, 2004).

K: Blair Walsh (Vikings, sixth, 2012).