How NFL rule changes for 2021 will impact the game - Fewer low blocks, expanded review and balanced holding calls - ESPN
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N.F.L. Will Experiment With Replay Reviews of Pass Interference - The New York Times
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N.F.L. Will Likely Use Replay to Confirm Illegal Hits - The New York Times
The NFL changed its replay rules after the Saints-Rams fiasco. Now comes the hard part. - The Washington Post
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