The Combine tells us nothing
In 2008, a study in the Journal of Strength and Conditioning Research by a team of University of Louisville scholars concluded: “Using correlation analysis, we find no consistent statistical relationship between combine tests and professional football performance. . . . Consequently, we question the overall usefulness of the combine.”
In 2011, analysts from the University of Georgia found very much the same and added this insight: Teams would be much better off watching game tape than players in singlets dashing around. “Past performance, collegiate performance engendered a stronger relationship with future NFL performance than a variety of physical ability tests administered during the NFL combine,” they wrote. “Unlike physical ability, past performance remained a valid predictor.”
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Here is a startling statistic: Seventeen players on their Super Bowl-winning roster, fully one-third of the team, never appeared at the NFL combine.
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Here’s another interesting predictor you won’t get at the combine: Teams that invest heavily in finding undrafted free agents tend to succeed. In 2017, SB Nation writer Levi Damien did an analysis of the NFL teams that carried the most undrafted free agents on their rosters. The top six teams all had winning records, including the Patriots.