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Stock Up: Dee Milliner, Alabama
Alabama's Dee Milliner doesn't flash elite quickness on the field, but that's mainly because he prefers to play a physical style of football. His 4.37 40 time at the combine shows that he has the speed needed to excel at the next level.
This excellent time increases his versatility as someone who could match up against both quicker and big-bodied targets. It'll be a shock if he makes out of the top 10.
Stock Up: Darius Slay, Mississippi State
Darius Slay was a little overlooked at Mississippi State because his teammate, Johnthan Banks, got more media attention. However, his production on the field was right on par with Banks. He tends to play a physical brand of football, but his 4.36 40 time shows his speed.
Slay still projects as a mid-round pick, but don't be surprised if he comes off the board in the early parts of the third round.
Stock Up: Desmond Trufant, Washington
Washington's Desmond Trufant is another physical cornerback who also showed that he has some quickness. His top-end speed was really the only major question mark facing his draft stock. It's safe to say Trufant locked down a spot in the second round with his 4.38 40 time.
Stock Up: Jamar Taylor, Boise State
The 40-yard dash shows the explosiveness of a prospect's first step and his long speed. However, the fluidity of a prospect's hips also plays a major role. Boise State's Jamar Taylor used the combine to show everyone he excels in both areas.
His combine performance backs up what he showed through out his college career.
Stock Up: Tyrann Mathieu, LSU
LSU's Tyrann Mathieu has seen his draft stock hit rock bottom after several off-the-field issues. The combine was his first opportunity to build some positive momentum. Mathieu posted a solid 4.50 40 time and competed well in the other events.
He has a long way to go before he rebuilds his stock, but this was a great start.
Stock Up: Shamarko Thomas, Syracuse
Outside of the draft community and Syracuse football fans, there are not a lot of people familiar with Syracuse's Shamarko Thomas. However, his name will be more recognizable after his solid showing at the combine.
Thomas displayed excellent athleticism to go along with his solid on-field production. His future is as a safety at the next level, not to mention a possible top-end special teams contributor.
Look for Thomas to come off the board somewhere in the fourth round.
Stock Up: Xavier Rhodes, Florida State
The combination of Xavier Rhodes' strong combine performance and Johnthan Banks' struggles will force a change in many rankings. Both are talented corners who like to play close to the line of scrimmage. However, Florida State's Rhodes posted a much better 40-time.
It's highly likely that Rhodes sealed up his spot as the No. 2 cornerback on most team's board.
Stock Down: Johnthan Banks, Mississippi State
The issue with focusing on a prospect's 40 time is that it overlooks their play on the field. This is something that will happen to Mississippi State's Banks. His 4.61 40 time was a major disappointment for the first-round hopeful.
Some teams will use this time to push him down down the board. However, Banks features the type of instincts and feel for the game to overcome this lack of top-end speed.
Stock Down: Tony Jefferson, Oklahoma
Oklahoma's Tony Jefferson is in a different situation than Banks, as his poor 40 time brings concerns about his range. Jefferson's play suggests that he gets by mainly with his athleticism and quickness. He has a tendency to take some poor angles and misread his keys.
This is why his 4.75 40 time is a red flag, as it increases his vulnerability for big plays.