So I have been asked to analyze the combine performance of the CBs. First though we need to talk about what makes a good CB. Of course straight-line speed is a plus, but it is not the ultimate measure, or the Raiders would have won the last 5 super bowls. Reaction time is critical - and that can be measured in the 10-yard split of the 40, as well as in the 20-yd shuttle and 3-cone drill. Ability to change direction is also paramount - that is gauged by the 20-yd shuttle (and 60-yd shuttle which few do) as well as the 3-cone drill.

You also have to be able to tackle, whether that is in run support on a running back or on a receiver after the catch (particularly on quick hitches). Tackling ability is not really tested at the combine but power is measured by broad jump and vertical leap. You can also infer power from the 10-yd split if you pair it with body weight. The other thing that gets talked about with corners is there overall size. A CB who is both fast and quick will struggle in the NFL if he is 5 foot 7 inches tall. There are too many big, strong fast WRs in the NFL that will take advantage of the height mismatch.

So what do I focus on when comparing CBs'combine results - this order

1. quickness

2. speed

3. strength

4. size

Once I have looked at those, then and only then, do I start watching tape and looking at in-game production. With that in mind here are the results from this year's combine. First the speed data since that seems to be what the media generally fawns over

Straight-line speed (with a little reaction time mixed in)

You'll notice that these are sorted by fastest 10-yd split. You'll also notice that the 10-yd splits are separated by 15 one hundredths of a second with the fastest being 1.46s and the slowest being 1.61s. Banks did himself no favors here - and that shows up in his speed score (which is one of the worst). Rhodes, McGee and Trufant all showed really well here - Rhodes particularly since he is 20 lbs heavier than the other two guys. Milliner was slightly slow out of the blocks, but showed great speed in his second 10 and "flying 20". The other guy who stood out here was Sanders Commings, the heaviest CB in the group at 216, his speed score was the best of the group at 114 because he was able to run a 4.41s 40 at 216 lbs. Nickell Robey, who has a great football name, shot himself in the foot here. At 5-7, 160 lbs you have to have Trindon Holliday speed to make it in the NFL - running a 4.53 does not qualify.

Quickness and Change of Direction

Unlike the 40, where everyone who was not injured participated, a few CBs decided not to run in one or both of these drills. The Quickness Score is similar to the speed score in that it uses the players weight and their CoD (20 yd shuttle plus 3-cone) value to get a score where 100 is average. Will Davis from USU really shined here. His 6.52 3-cone was a full 0.17s faster than any other CB (best overall at the combine by 0.01s). His 20-yd shuttle was well above average. Even normalizing for his smaller size (at 186 he is on the lower end), his quickness quickness score was the best of the bunch. 4 other guys showed superb quickness: Gratz, Anthony, Ryan and Webb. Xavier Rhodes chose not to do the quickness drills. Desmond Trunfant ran a great 20-yard shuttle and decided to forego the 3-cone.

The Power Drills

I'm guessing that the guys with the lowest explosion numbers are probably not going to make it as starting corners in the league, but maybe maybe the honey badger could take down AP on a sweep one-on-one. NAH. That's not happening. The guys on the top of this list probably have the strength and/or power to tackle well, even if they can't translate that strength/power into made tackles.

Ok so there are a few guys that popped out of this study that were unknowns to me before this (e.g. KK hasn't profiled them - yet): Dwayne Gratz, Will Davis, Sanders Commings and B.W. Webb

Dwayne Gratz

via www.rantsports.com

Gratz has good size for an NFL. He was a three year starter for UConn although he appeared in 13 games as freshman. He is not afraid to come up in run support. Here are his career stats

49 games

187 tackles

10 TFL

8 Int (3 TDs - 1 FR TD)

28 PBU

1 FF

Gratz write-up at nfl.com

I like his strengths write-up

"Combines NFL height and overall strength. Stays low in his stance and when opening up in bail coverage. Good closing ability, quick to attack short passes to knock them away or make the tough tackle. Aggressive hitter, can put his helmet on the ball or cut down ballcarriers equally well near the line or in space. Used as a blitzer regularly and is fast to close off cutback lanes on run plays when uncovered. Quick hands and feet to consistently beat receiver blocks. Capable of making the interception with his hands or body on poor throws, fair ball skills to grab low or high passes."

His draft stock moved up with his performance at the combine. He was projected to be a 5th round pick prior to the combine. He is now being projected to go in the 2-3 round. NFL.com compares him to Bradley Fletcher, the current nickel corner for the Rams.

Will Davis

via bloximages.chicago2.vip.townnews.com

Will Davis is a slightly undersized (by NFL standards) CB weighing in at 186 lbs at the combine. His straight-line speed was not great (both his 40 and his 10-yd split were below average). Where he shined was in his quickness. He showed that he was the quickest CB at the combine. Davis' 3-cone is better than what Josh Robinson did last year (best CB in 2012) and Patrick Peterson did in 2011. Davis is the anti-Alphonso Smith (who had good straight-line speed, but no quickness). Davis is leaving USU after playing for two years. He only played one year of high school football, so he is still learning the position of CB.

His career stats are below

26 games (18 starts)

101 tackles

8 TFL

23 PBU

5 Ints (1 pick 6)

3 QB hurries

Davis at nfl.com

I like his strengths - particularly how he is listed as having quick feet (which showed in the combine) and fluid hips. His listed weaknesses scare me a little

"Overaggressive nature. Susceptible to getting beat by double moves. Lacks the recovery speed to catch up to a receiver that has run by him. Has issues with beating blocks from the receiver. Will lower his head and give sub-par tackling efforts."

I would not mind seeing us draft him. His is currently projected as a 4th rounder. NFL.com compares him to Aulternan Verner, the #2 corner for the Titans.

Sanders Commings

via www.accessnorthga.com

Commings is the biggest corner in this draft at 216 lbs, but he runs well for his size. He is built like many of the WRs that he faced in the SEC - big and fast - though he is not overly tall. His speed score was the best of the CBs at the combine - 114. He is middle of the pack in terms of quicknes and he was average to above average in power (not sure why he opted out of the bench press?). Commings appeared in every game during his 4 years at UGA.

51 games

142 tackles

6 TFL

1 sack

8 Int

16 PBU

3 QB hurries

1 FF

His low number of passes defended is somewhat worrisome, but they may not have been throwing at the receiver that he was covering.

Commings at nfl.com

They compare him to Brandon Browner, the #2 corner for the Seachickens. After reading up on his weaknesses (slow feet) and his character red flags (domestic abuse arrest) - I doubt we draft him.

B.W. Webb

via cdn.bleacherreport.net

Webb played for William and Mary at the FCS level. So I am not going to bother posting his stats here. What I am going to mention is how this guy is good combination of strength and quickness. Webb is currently projected to go in the 3rd round after improving his draft stock at the combine.

I'll show what nfl.com writes as their final analysis on him.

"Webb has been a star since picking off Virginia three times in the Tribe’s 2009 opening-weekend shocker. The four-year starter has the hands and cover skills (if average size) to be one of the top “small school” prospects in the draft. He projects as at least a reliable nickel back on defense and a regular contributor on special teams -– and possibly more (he has the athleticism and cover skills to play outside), much like recent third-round picks from smaller schools Dwight Bentley (Louisiana-Lafayette) and Lardarius Webb (Nicholls State). After showing he can hold his own at the Senior Bowl, and if he performs well at the combine, his stock could skyrocket to the third round or higher."

I have always been fond of tenacious CBs like Chris Harris so I would not mind if the Broncos got this guy.

What does any of this mean?

Here are the top 20 CBs in the NFL from last year in terms of % of first downs or touchdowns allowed per snap. IMO this is the best measure of how well a CB is playing.

Now here are the same guys' combine results (pro-day results for a few of these guys, notably Harris) in terms of quickness and speed.

What you will notice about this is that only two of these guys had poor performances at the combine, the aforementioned Sherman and Josh Wilson. Josh Wilson may be quick - there is no data. You could make the argument that Verner's 40 time constitutes a poor combine as well. My conclusion is this, none of the top corners in the league were below average in both speed and quickness at the combine. Now, correlation is not causation, so that does not mean that being fast and quick will make you a great NFL CB. What is does mean is that the chances of being a great NFL cornerback without being fast and/or quick are very slim.

So what does this mean for a guy like Jonathan Banks? Banks had a poor combine his speed score was 81.9 and his quickness score was 89.2. Banks ran a 4.51s 40 at his pro-day which would improve his speed score to 89.4 - better but still not great. There are no NFL CBs in the top 20 from last year with both a speed score and quickness score below 90. From that I would not want the Broncos to get Banks, but others are free to disagree.

The real question comes down to who do you like and when do you like them - so sound on in the comments and the poll.