The NFL Combine begins in two days, and many questions will be answered, many mocks will be completely rearranged, and many teams' draft boards will shift drastically.  This year is deep once again at Offensive Tackle, and once again somewhat thin at Offensive Guard and Center.  I was originally going to combine the Guards and Centers into one article, but I changed my mind.  Here are the top Offensive Guard prospects in the upcoming draft:

(Feel free to let me know who I left out)

Duke Robinson, Oklahoma  6'5", 335

Duke Robinson is by far the best Guard in the upcoming draft, and probably the only first rounder.  Some mocks have him falling to the top of the second, but I honestly don't see that happening.

Robinson has been a staple on the Oklahoma offensive line for the last 3 seasons.  His freshman season, he saw action at left tackle, but moved to guard his sophomore year.  His has great size, and is incredibly strong, especially in his lower body.  He is very well known for his ability to drive  defensive linemen into the ground.

The only questions about Duke are about his level of commitment at times, and his ability to pick up delayed blitzes.  I saw a couple of games last season where Robinson seemed to get better as the game went on, like he had to get going before being effective.  But once he did build up momentum, he was a beast.

Duke Robinson will be an immediate starter in the NFL, and will be seen playing on Sundays for years to come.

Highlights (pops)

Herman Johnson, LSU, 6'7", 375

Herman Johnson is an absolute behemoth of a man.  He is known to be the largest baby born in Louisiana, weighing in at 15lbs, 14ozs.  I have met him personally, and can tell you that in the offseason, he pushes 390-395 lbs.

Johnson is incredibly strong, as can be imagined, and on the inside will crush defensive linemen.  Pancake blocks and knock-downs are an every-game thing for Herman Johnson.  He has very long arms, and once he gets a hold of a defensive player, you can bet he will make him pay.  On the inside, cannot be moved.

Johnson is also known to be sluggish at times.  His conditioning is surprisingly not an issue, but it has been said that he doesn't always play up to his size and ability.  He doesn't move very well laterally, but has been productive as a pulling guard when called for.

Johnson will eventually be a starting Guard in the NFL, but may need a season to develop.

Kraig Urbik, Wisconsin, 6'6", 325

Kraig Urbik has a ton of experience under his belt.  He played all 4 years with the Badgers, and registered 49 starts.  He is known to be a very intelligent football player, and have great technique.  Urbik has good size to play on the inside at the pro-level.

Wisconsin had a ton of penalty flags thrown against them last season, but very few were against Urbik.  He did well with pass blocking, giving up very few sacks.  Urbik is a player that a lot of teams are interested in seeing at the combine.  Most view him as a 2nd day pick, but many teams will be keeping an eye on him, as he will undoubtedly learn very quickly, and be able to provide instant depth for whomever drafts him.

Tyronne Green, Auburn, 6'3", 305

Tyronne Green is definately smaller than most NFL teams would prefer their Guards to be.  But, he has faced off against many of the best pass-rushers and run-stuffers in the college ranks, and very rarely got beat.

Green is surprisingly strong for his smaller frame, and has tremendous speed.  He can get to the 2nd level of defenders when necessary.  Green plays hard... very hard.  He has proven to be a good listener and student of the game, contantly wanting to learn more.  He has been a natural leader for the Auburn Tigers, and has earned the respect of everyone in the lockerroom.

Tyronne has been trying to add some bulk to his frame, and will need some extra coaching at the NFL level on his technique.  But Green is very well-known for his work ethic... and  I certainly expect to see him in someone's starting lineup within the next couple of seasons.