The make-or-break scouting event for every prospective NFL draftee for 2015 begins at the draft combine in Indianapolis. No single event, outside of a quarterback's throwing session on campus, comes close to having the shaping and formative impact on athletes' futures than these few days to come. Every single head coach, executive and scout, and even a few owners are in attendance. A player who performs dramatically in the testing, one-on-one meetings and position workouts can see his draft round dramatically improve. Players who disappoint may see precipitous decrease in their value.

Most potential draftees have been training for the past six weeks at a combine preparation facility. They have been on strict nutritional diets. They have worked with trainers and position specific coaches to perform the five drills and to show up well in the workouts. This has become a highly competitive business. Players freed from the practice and play season regimen can show dramatic improvement in their physical capacity.

The players arrive by position on a staggered basis over the seven days. They may have traveled a long distance and be greeted with colder weather. Most arrive somewhat fatigued, and the scheduling can be so intense that it prolongs their weariness. First up are the physicals. Players are measured and weighed like beef on the hoof. A series of medical personnel administer "the mother of all physicals." If a player's knee is slightly tender on arrival, it is throbbing after having a series of doctors probe it.

There are five physical drills that are offered. The first is running a 40-yard dash. In a speed-centric league, there is an obsession with 40 time. A defensive back or wide receiver who runs in the 4.3 range or below will see his draft stock accelerate rapidly. A sub-par 40 for a running back will produce a plummet in assessment. Linemen may be measured more by their time in the first ten or twenty yards. Two different times I had wide receivers who were the fastest player in the combine -- they both jumped into the first round.

The next drill is a bench press of 225 pounds. This is critical for offensive and defensive lineman. Players with long arms have a greater distance to push and may have difficulty matching their short armed competitors in number. I represented Igor Olshansky, defensive end from Oregon who set the record of 43 lifts back in 2004. It was broken the next year. Players are then tested in a vertical leap to see how high they can get off the ground. For defensive backs and wide receivers this is an important measure. Players then do a standing broad jump and a lateral cone drill to show maneuverability.

Teams have the opportunity to meet with players one-on-one in sessions that may include a coach, general manager, and coordinator or position coach. This is the chance to look a draftee in the eyes and make judgments about character and coachability. This is an athlete's chance to clarify any aberrational behavior in his past. A gifted athlete like Florida State quarterback Jameis Winston has the opportunity to explain himself and quiet concerns.

Players are then able to work out at their position on the field. This is the chance for teams to see a player up close and assess his skill set in real time. For a quarterback who is not a surefire first-round draft pick, throwing in this forum can truly help his status. It is harder to make an impression, however, when he is throwing to receivers that he has never thrown to before.

The draft may occur in April and May, but many of the fates of college hopefuls rest on their ability to perform under pressure in the next week.

-- Leigh Steinberg has represented many of the most successful athletes and coaches in football, basketball, baseball, hockey, boxing and golf, including the first overall pick in the NFL draft an unprecedented eight times, among more than 60 first-round selections. His clients have included Hall of Fame quarterbacks Steve Young, Troy Aikman and Warren Moon, and he served as the inspiration for the movie "Jerry Maguire." Follow him on Twitter @leighsteinberg.

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