Three teams with new coaches will begin voluntary offseason workouts on Monday: San Francisco, Philadelphia and Cleveland.
The NFL announced spring workout dates Friday, with most mandatory minicamps scheduled for mid-June.
San Francisco hired Chip Kelly, Philadelphia replaced Kelly with Doug Peterson, and Hue Jackson is now coaching the Browns.
Other teams that changed coaching staffs and can begin early activities - strength and conditioning and physical rehabilitation only - are Miami with Adam Gase, Tampa Bay with Dirk Koetter, and the New York Giants with Ben McAdoo. They will start on April 11.
Under the labor agreement, there are three phases to the voluntary programs. The second phase allows on-field workouts with individual player instruction and drills, as well as team practices with no live contact or offense versus defense drills.
The third phase allows 10 days over four weeks of organized team activities. OTAs consist of 7-on-7, 9-on-7, and 11-on-11 drills, but no live contact.
''When you bring in new ideas and new opinions, it's twofold,'' Giants defensive coordinator Steve Spagnuolo said. ''You can gather new ideas about what other people have been doing, and I think we've got some great guys here. And it's always good when someone comes in and says, `Why are you calling it that?' or `Why are you doing this?' So that's been really good. The give and take and the interaction has been great.''
The first required minicamps will be staged June 7-9, with many teams holding them the following week. Opening on June 7 will be minicamps for Arizona, Cleveland, Denver, Indianapolis, New England, Philadelphia and San Francisco.
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