Glenn, Kalil lead impressive group of offensive linemen at combine

The combine got under way in earnest Saturday as the offensive linemen took to the field of Lucas Oil Stadium to be physically tested and then work through a battery of blocking drills. It was a very athletic group of blockers who pleased scouts as most exceeded expectations with their outstanding physical skills. Here's a look at the risers and sliders from the group.

Cordy Glenn, Georgia: Glenn was impressive from the get-go, and his draft stock continues to move North. Glenn started his combine by completing 31 repetitions of 225 pounds on the bench press, a terrific result for a lineman with arms in excess of 35 inches. Glenn displayed surprising athleticism as he ran just under five seconds during his first attempt of the 40 (4.99 hand timed). He later looked outstanding in drills, displaying quick footwork, power and solid fundamentals. Glenn was considered a possible late first-round pick entering the combine, but after today many are grading him as a top-25 choice.

Matt Kalil, USC: Kalil started strong, completing 30 reps on the bench, a number that exceeded expectations. His 40 time, which clocked 4.98 seconds, was another good mark. Kalil really stood out in drills, looking as good as any offensive lineman who took to the field this morning. He was explosive, powerful yet at the same time smooth and fluid. If there was any doubt that Kalil was a top-five pick in April's draft, it was erased today.

Donald Stephenson, Oklahoma: Stephenson, who was not rated as a draftable player entering the season, continued to improve on his solid senior season at the combine. He was one of the most athletic offensive linemen on the field, turning in 40 times under five seconds and looking very good in drills. Stephenson was quick and fluid, displaying top footwork in pass protection and good movement skills all morning. He has to iron out some of his mechanics, but Stephenson improved his stock and has moved into the draft's middle rounds.

Riley Reiff, Iowa: Reiff ran reasonably well, breaking the 5.2-second mark on a number of watches, which included an impressive 10-yard split of 1.75 seconds. During drills Reiff looked quick, fluid and explosive. Though there's been a variety of opinions where Reiff will line up at the next level, after today most scouts feel he has all the skills to hold down left tackle.

David DeCastro, Stanford: DeCastro's combine marks were nothing out of the ordinary, though his bench mark of 34 reps was solid. The big blocker did stand out during drills and impressed scouts. DeCastro was fluid, looked natural in all the drills and was also effective when asked to snap from center. DeCastro did the little things well and showed he pays attention to the details of his position, two more reasons why he's making a march into the early part of round one.

Adam Gettis, Iowa: Few linemen equaled the athleticism of Gettis during the testing portion of the combine. He was a last-minute invite yet one of the fastest blockers, timing under five seconds in the 40. His 10-yard split, a more important measure for offensive linemen, was under 1.7 seconds, which is a tremendous mark. His marks of 31.5 inches in the vertical jump and broad jump of 9 feet, 4 inches were also superb. Gettis looked slightly stiff during drills, and his mechanics need polish, yet his underlying ability and upside potential were evident to all on hand.

Jeff Allen, Illinois: Allen is truly one of the sleepers on the offensive line. His early marks of 5.15 seconds in the 40 and 26 reps on the bench were solid. Later in the day Allen really stood out during drills. He looked athletic, fundamentally sound and moved incredibly well, showing both quickness and body control. His combine workout along with the ability to line up at several positions could have Allen selected earlier in the draft than most people presently predict.

Philip Blake, Baylor: Blake's 40 times were adequate, just over 5.10 seconds, yet he was another who stood out when it was time for the offensive line drills. The versatile lineman looked incredibly athletic in all drills, displaying quickness, movement skills and balance. Teams believe Blake can line up at guard or center and after today feel he has starting potential.

Dustin Waldron, Portland State: The small-school tackle showed a lot of what scouts hoped to see. His 5.35-second 40 was nothing outstanding, yet his 10-yard split, which stopped watches at just over 1.7 seconds, was notable. Waldron looked quick and athletic throughout the drilling session.

Amini Silatolu, Midwestern State: Silatolu is another small-school lineman who looked better in drills than during the testing phase. He displayed incredible quickness, footwork and terrific movement skills. Silatolu also has an impressive blocker build, and scouts feel he could develop into a starter at the in due time.

Mitchell Schwartz, California: Schwartz is a lineman who won't impress scouts with his athleticism, and he didn't during the testing phase Saturday morning. Yet once the drills started it was a completely different story. Schwartz was fundamentally impressive and displayed great mechanics in all his drills. He leaves the combine with teams believing he offers starting potential at right tackle.

Zebrie Sanders, Florida State: Sanders was tabbed as a potential first-round pick by many after the 2011 season. He struggled during the Senior Bowl and turned in a poor combine workout Saturday. Sanders struggled to get under 5.5 seconds in the 40, and his 10-yard splits were pedestrian. He looked sluggish and slow-footed during all drills.

Josh Oglesby, Wisconsin: Oglesby displayed next-level size during weigh-ins yet does not have the athleticism necessary to make an NFL roster. He struggled to run faster than 5.8 seconds in the 40 then lumbered around and looked heavy-footed during drills.

Rishaw Johnson, Cal-PA: Johnson ran fast in the 40 and tested well in the jumps. His drills were another story. Johnson was off balance, haphazard in his movement and neither smooth nor fluid. Worst of all, Johnson experienced the wrath of coaches after he was unable to follow instructions on how to complete drills.

Senio Kelemete, Washington: Entering the combine, scouts lauded Kelemete's athleticism, yet the former Husky blocker showed none of that Saturday. After completing a paltry 21 reps on the bench, Kelemete was unable to get under 5.5 seconds in the 40, and his 10-yard split was slow (1.85 seconds). Those latter two marks will not sit well for a lineman most project as a zone blocker.

Stanford tackle Jonathan Martin had been struggling with flu-like symptoms leading up to the combine and missed almost an entire week of training. After initially choosing not to work out at the combine, Martin reversed course and decided to participate in position drills after scouts challenged him during interviews. Martin did reasonably well, and the way he toughed the day out will sit well with scouts.