2012 NFL Draft: Best-Case and Worst-Case Scenarios for Draft's Top 5 Talents

The 2012 NFL draft kicks off on April 26th, and among the most heavily scrutinized selections will be the top five overall picks.

These collegiate stars will be expected to step in an make an immediate impact on their new NFL clubs.

Here's a look at the prospects for those top five selections, along with the best-case scenarios that would start them well on their way to NFL stardom, and the worst-case scenarios that could set that ascension back for a while.

Andrew Luck, QB, Stanford

After throwing for over 9,300 yards over the past three seasons in a pro-style offense at Stanford, quarterback Andrew Luck is the presumptive favorite to be chosen first overall in this April's draft.

Best-Case Scenario: The Colts improve the pass protection and receiving options at Luck's disposal, and the 6'4", 310-pound signal-caller flirts with Cam Newton's rookie passing record while the Colts go 6-10.

Worst-Case Scenario: The Colts offensive line is a nightmare, and Luck's confidence takes a beating as he spends the entire 2012 season either running for his life or flat on his back.

Robert Griffin III, QB, Baylor

Baylor quarterback Robert Griffin III was the 2011 recipient of the Heisman Trophy, and after sacrificing two extra first-round picks and a second, there's very little doubt that the Washington Redskins will make Griffin the second overall pick.

Best-Case Scenario: Griffin's early visits with Washington offensive coordinator Kyle Shanahan pay off. Griffin hits the ground running, and "RG3" tears up the NFL much in the way that Cam Newton did a season ago.

Worst-Case Scenario: Griffin struggles to learn the Redskins' pro-style offense. He comes out of the gate slowly, and by mid-season, the boo-birds have taken up residence in the nation's capital.

Matt Kalil, OT, USC

USC offensive tackle Matt Kalil is universally considered to be the top left tackle prospect after a junior season in which the 6'5", 306-pound All-American didn't allow a sack.

Kalil will all but certainly be a top-five pick in this April's NFL draft.

Best-Case Scenario: Kalil steps into the starting lineup on day one and plays as advertised, helping Minnesota Vikings quarterback Christian Ponder develop by protecting his blind side.

Worst-Case Scenario: Kalil gets off to a rocky start, and a Vikings line that surrendered the fifth-most sacks in the National Football League in 2011 continues to be an absolute sieve.

Morris Claiborne, CB, LSU

Cornerback Morris Claiborne of LSU is the top cornerback prospect in this year's draft class.

Although his incredibly low score of four on the Wonderlic test is cause for some concern, it's unlikely that that will be enough to drop Claiborne from the Top Five.

Best-Case Scenario: Claiborne hits the NFL much like he hit the SEC, and the 5'11", 188-pounder becomes an immediate contributor on a Tampa Bay defense that badly needs secondary help.

Worst-Case Scenario: Claiborne's reported learning disability makes picking up complicated NFL coverages more difficult, and that lengthened learning curve results in Claiborne being relegated to a reserve role as a rookie.

5. Trent Richardson, RB, Alabama

Trent Richardson is college football's top running back prospect after topping 2,000 total yards and winning the Doak Walker Award as college football's top running back in 2011.

There's a very good chance that Richardson will be the first ball-carrier taken in the top five since 2008.

Best-Case Scenario: Richardson hits the ground running in the NFL just like he did in college, topping 1,500 rushing yards and instilling a measure of hope in the forlorn hearts of Cleveland Browns fans.

Worst-Case Scenario: Richardson's surgically repaired knee continues to be an issue all season long, leading the notoriously nihilistic Cleveland fanbase to chalk Richardson up to just another wasted first-round pick.