NORMAN — Former Oklahoma tight end Trent Smith has some advice for the Sooners players about to learn their NFL Draft destiny: "Check your attitude and how good you think you are at the door, because it’s a different world up there.” Smith, who caught more passes than any tight end in school history, can speak from experience about how tough it is to make it in the NFL. He was a seventh-round pick in the 2003 draft and got to play in only five games over the next four years. "Here you might be one of the best players in all of college football,” said Smith, who returned to Owen Field this month for a flag football game between former Oklahoma players. "You get up there and you’re just one of the better guys on one team. "You’re going against the best of the best every single day in practice and on the field. Even the practice squad guys have the potential to go on and be All-Pros. It’s just ridiculous the amount of talent.” In Bob Stoops’ first nine years as Oklahoma’s coach, the Sooners have had 36 players drafted — an average of four per year. But college stardom has not necessarily been an indicator of NFL success. Tailback Adrian Peterson and lineman Jammal Brown were each named to the All-Pro team in their first two seasons, and defensive tackle Tommie Harris was a second-team pick in 2005. But during a stretch that has produced six Big 12 titles, a national championship and five other BCS bowl appearances, many of the team’s best players haven’t blossomed at the next level. Jason White, the 2003 Heisman Trophy winner, and Josh Heupel, the 2000 Heisman runner-up, never played a snap in the NFL. White, who had two surgically repaired knees, didn’t even get drafted, while Heupel was a sixth-round pick who got cut before the season started because of an injury. Antonio Perkins was the 2003 All-America all-purpose player, the same spot filled by Reggie Bush and Maurice Jones-Drew the following two years, but never really made an impact in the NFL and played in only six games after being a fourth-round pick in 2005. Derrick Strait, an All-America cornerback regarded as a standard-bearer in Norman, started only five games in his three seasons after being drafted in the third round in 2004. The bottom line is that only the elite players make it in the NFL. Larry Birdine, a defensive end who had seven sacks in the Sooners’ run to the Orange Bowl five years ago, is now toiling away on the Tennessee Titans’ practice squad in hopes of making the roster. "It’s fun but it’s a lot of work,” Birdine said. "You’ve definitely got to come prepared every day and be consistent if you plan to stay. All you need is a fair shot, and if you get that, the rest is up to you.” Coming out of college, a first-round pedigree starts a career out in the right direction. Of the eight first-round picks in the Stoops era, seven have become fixtures in their team’s starting lineup and the other, safety Andre Woolfolk, started 12 games in a four-year career plagued by injuries.