OPINION

By Vinnie Iyer

updated 4:59 p.m. ET Feb. 27, 2008

It happens at every Combine: Some top-rated NFL draft prospect makes jaws drop with his time in the 40-yard dash, and in most years, some teams — most notably the speed-happy Raiders—push that prospect right to the top of their draft boards.

This year’s model is that Ferrari from Arkansas, running back Darren McFadden, a two-time Heisman Trophy runner-up. McFadden strengthened his case to be the first running back off the board in April by running the 40 in a sweet 4.33 seconds.

That actually was second among players at the position — East Carolina’s Chris Johnson ran a 4.24 — but considering his SEC pedigree and individual laurels, McFadden is reaffirming that he can be a big-time performer in the NFL.

But while the 40-yard dash is the most glamorous and most popular pre-draft measuring tool, it’s not a make-or-break event by any means. If it were, track stars would consistently become football stars. From Renaldo Nehemiah and others who have tried and failed over the decades, we know that just doesn’t happen.

And how often do running backs get a chance to run 40 yards down an NFL field unimpeded? And when that happens, it usually is the result of five bigger, stronger, slower guys imposing their will to open that kind of a lane.

Let’s look at the previous three years of running back prospects. And let’s take into account all the best recorded 40 times we had noted, whether it was at the Combine or in a personal or pro day workout. In 2005, Cal’s J.J. Arrington (Cardinals) was the top major-college back with his 4.4 40. Miami’s Frank Gore (49ers), with his college history of knee injuries, finished 54^th with a 4.65.

Since then, Arrington has yet to break 1,000 yards from scrimmage, while Gore has the most yards from scrimmage than anyone in the '05 class. As for the most rushing touchdowns from the '05 class, that’s Marion Barber, who ran the 21^st-fastest pre-draft 40.

But in the same year, maybe someone should have paid more attention to Notre Dame’s Ryan Grant and his 4.43, which was good for a fourth-place tie. He went undrafted; three seasons later, he is a big-play runner for the Packers.

The gold medal in 2006, not surprisingly, went to USC’s Reggie Bush (Saints), and two other dynamic rookies-to-be, UCLA’s Maurice Jones-Drew (Jaguars) and LSU’s Joseph Addai (Colts), joined him in the top six.

Last year, not surprisingly, Oklahoma’s Adrian Peterson (Vikings) and Cal’s Marshawn Lynch (Bills) both were among the top 10 in 40 times. Ahmad Bradshaw, on the other hand, probably wouldn’t have lasted long enough to become a seventh-round steal for the Giants if he hadn’t “unimpressed” most teams with his 28^th-best 4.57 mark.

For McFadden, a dazzling dash just keeps him elite. For Johnson, his stock won’t necessarily shoot up.

When it comes to translating the 40-yard times into NFL performance, the results are mixed. A running back needs to have many other assets than, well, running well. Size, strength, power and quickness all carry their own weight, as does going to a team with good run blocking and a system designed for a back’s particular style.

As for wide receivers, you can put their 40-yard times in the shredder based on what has happened recently.

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Among the top 10 40-yard dashers in ‘05, from 4.26 to 4:39 seconds: Jerome Mathis, Troy Williamson, Courtney Roby, Matt Jones, Craphonso Thorpe, Mark Bradley and Terrence Murphy. The other three went undrafted. Braylon Edwards easily has been the best wide receiver of the class, despite posting a 4.45, tied for 21^st-best.

In ‘06, only the Steelers’ Santonio Holmes (4.35) delivered on the promise he showed with his top-10 finish in the 40. And in ‘07, scouts shouldn’t have really needed solid 40s to be convinced of Calvin Johnson and Ted Ginn Jr.’s explosive potential—the other top speedsters in their class have yet to show anything as receivers.

The Combine speed drills may be great training if they ever bring back the Superstars competition, where football players had to run, swim, hoop, weightlift, row, bike, bowl (yes, bowl) and negotiate an obstacle course to prove their athletic worthiness.

The NFL is a very fast game, but it isn’t played in a straight line and its results can’t be measured by a stopwatch. The only result that matters in football is winning, and the best way to distinguish winning backs and receivers from the rest remains how they do in games.

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