The on-field workouts begin Thursday at the NFL's scouting combine inside Lucas Oil Stadium in Indianapolis.
A look at what you need to know:
The workouts: 7-11 p.m. ET (NFL Network), quarterbacks, wide receivers and tight ends do the vertical jump, broad jump, 40-yard dash, shuttle drills and position drills.
And ... : The offensive linemen and running backs will do bench press, defensive linemen and linebackers have their medical exams and defensive backs will be measured and weighed and go through psychological testing.
The record holders: Former University of Washington wide receiver John Ross -- now with the Cincinnati Bengals -- set what is considered the record for the 40-yard dash in the combine's electronic timing format that began in 1999 with a 4.