Randy Johnson shines in South Florida

DAVIE, Fla. -- Speed and skill ruled the day as the Under Armour Combine schedule kicked off Sunday at the Miami Dolphins Training Complex. There were plenty of skill-position players that produced great testing numbers, including some of the faster times seen on the combine tour in recent years.

There were also some breakout performances by a couple of emerging stars during the competition and one-on-one segments, and a number of players from the ESPNU 150 Watch List were as good as advertised.

All-American performance
Randy Johnson (Miami, Fla./Norland) posted elite testing numbers and flashed the football skill set that earned him an early invitation to the Under Armour All-America Game in 2012. Johnson, a Miami commit, ran the 40-yard dash in the high 4.4-second range and had one of the day's best short shuttle times of 4.3 seconds, showing outstanding quickness and change-of-direction skill.

When it came time to competing, the dynamic athlete took reps at both corner and running back, demonstrating great versatility and an upper-tier level of quickness and ball skills. He proved an impossible matchup out of the backfield as a pass catcher with his quick, fluid cuts and great burst out of his breaks.

As a corner, we liked the aggressiveness he showed pressing receivers off the line and great acceleration closing on the ball. His leaping and jump-ball skills were also impressive. Johnson is being recruited to Miami as a running back, but he could also play corner at the next level as well as return kicks.

Shedding the 'sleeper' tag
ATH Herb Waters (Homestead, Fla./Homestead) is still a little under the radar early on the recruiting trail but that might change after his performance on Sunday.

The rangy athlete checked in at just under 6-feet and showed good testing speed (4.51 in the 40) and lateral quickness (4.22 in the short shuttle). He also flashed great play-speed and during one-on-ones as well. While he showed the athleticism, range and ball skills to play safety at the college level, he took most of his reps at receiver and consistently came up with the big grab.

He is a sleek athlete, smooth in his movement skills and was difficult to mirror off the line and out of his breaks. Waters showed the top-end speed to separate vertically and great jump-ball skills on a couple of grabs in the red zone. Waters is a dynamic athlete that had one of the better performances on the day.

Running back group is deep, talented
Proving there were plenty of talented running backs at the combine, Dami Ayoola (Ft. Lauderdale, Fla./St. Thomas Aquinas) also had a very solid day. Ayoola has very good body composition, showing good lower-body thickness and explosion as well as great upper body strength (21 repetitions of the 185-pound bench press).

He also showed good speed and soft hands out of the backfield. His day really supplemented the well-rounded tools we have seen on early film evaluations. Rutgers and Iowa have offered, and he has a favorable style for those offenses.

However, the best overall performance may have been by a 2014 rising sophomore. Sony Michel (Plantation, Fla./American Heritage) had testing numbers that were off the charts.

Michel had a 4.46 40, 6.86-second three-cone time and a 4.22 short shuttle. The footwork, lateral cutting quickness and balance he displayed on his compact 194-pound frame during drills were outstanding. Michel can catch the football as well, and he proved too quick and fluid in space for linebackers to try and mirror as a pass catcher. His supreme blend of speed, quickness and burst at this stage is rare.

That has led to mindboggling stats, including a 1,500-plus yard plus performance as a freshman as well as early offers from Miami and FSU.

Combine freak
S Deon Bush (Miami, Fla./Christopher Columbus) is earning the early label as one of the top safeties in the Sunshine State for 2012. While a slight groin injury kept him out of one-on-ones and seven-on-sevens, his testing numbers during the combine segment were outstanding.

Bush, a rangy safety, measured in at close to 6-foot-1 and 180-pounds and ran a blazing 40 yard dash of 4.44 seconds. He moved quickly and fluidly through the three-cone drill for a taller athlete, bending and getting low out of his cuts. His vertical was a very respectable 34 inches, he hammered out 17 reps on the bench and showed good lower-body explosion with a 10-foot-5 broad jump.

• DB Daniel Gray (Ft. Lauderdale, Fla./Boyd Anderson) slipped a few times on the starts of his 40s but still ran in the low 4.5 range and showed excellent acceleration and BCS-level type makeup speed in coverage.

• It was not a great overall showing at the quarterback position, but Gunnar Holcombe (Ft. Lauderdale, Fla./University School) and 2013 passer Tyler Cogswell (Plantation, Fla./American Heritage) separated themselves with good performances.

Holcombe, who already has offers from South Florida, Wisconsin and Rutgers, has a quick, compact delivery with some zip. His throwing mechanics are a bit unrefined, as he tends to push the ball at times with a lower release point, but he flashed good RPMs and fit the ball into tight windows throughout the day. He also showed he could drop the ball over the top of downfield coverage. Cogswell has good size and a lot of raw tools to develop over the next few years.

• Teammates Lucas Thompson and Marcel Harris of West Orange High School are two back-end defenders to keep your eye on as they possess good size and showed impressive range and athleticism patrolling the deep zone.

• Running back Gary Holmes Jr. (Loxahatchee, Fla./Seminole Ridge) had a good overall showing including one of the faster 40s of the day with a blazing 4.39 seconds.

• Running back Brian Grove (West Palm Beach, Fla./Kings Academy) posted some of the best collective times of the day, headlined by a 4.43 second 40 and a 4.28 short shuttle.

Billy Tucker is a recruiting coordinator for ESPN Recruiting and has close to a decade of coaching experience at the college and high school levels.