Russell's road back to the NFL will be a difficult one. (Getty Images)

Former Raiders quarterback and 2007 first-overall pick JaMarcus Russell last threw an NFL pass on Jan. 3, 2010. In the three years since, he's attempted a comeback, had his mentor John Lucas call it quits, and been linked to purple drank (among many, many other things).

Last month, Russell announced that he was mounting another NFL comeback, although at this point it's hard to take him seriously given the opportunities and talent he had previously squandered. It also didn't help that Russell weighed over 300 pounds. (With Jared Lorenzen out of the league, too, the heavy-set quarterback hasn't taken off like their wildcat or the read-option brethren.)

But four weeks later and Russell is still at it. His last progress report, courtesy of Bleacher Report, is, well, sobering: the former LSU star ran a 5.2 40-yard dash. The goal is to get down to 4.8.

Out of curiosity more than for comparison, here are the best and worst 40 times for quarterbacks who made NFL rosters from recent combines:

2012: best - Robert Griffin III, 4.41; worst - Nick Foles, 5.14
2011: best - Tyrod Taylor, 4.47; worst - Ryan Mallet, 5.12
2010: best - Sam Bradford, 4.70; worst - Mike Kafka, 5.04
2009: best - Stephen McGee, 4.66; worst - Graham Harrell, 5.14
2008: best - Dennis Dixon, 4.60; worst - Erik Ainge, 4.98
2007: best - Troy Smith, 4.62; worst - Jordan Palmer, 4.98

(Worth pointing out: Russell ran an 4.84 at the combine in '07.)

Other measurables from Russell's latest session: a vertical jump of 29 inches (the goal is 33), and 7-4 in the broad jump (the goal is 9 feet).

"I'm heavier than normal," Russell said, via AL.com's Mark Inabinett. "This is just getting some perspective on where we're at. Once the pro day comes, I'll be in some great shape and my numbers will excel."

This is where the skeptics roll their eyes with the "Yeah, we've heard this before" look on their faces. And understandably so given how Russell's forgettable three-year career played out, not to mention the four years of fallout that followed.

But maybe this time will be different. Seems optimistic given his history (and his present -- Russell still looks like an offensive lineman), but we'll continue to follow his progress because everybody loves a good redemption story.

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