.Source: 49ers have Aiyuk field structure with Browns, Patriots NBC Athletics Bay AreaBrandon Aiyuk field requirement: 49ers WR more probable to be handled than receive expansion coming from San Francisco, per document CBS SportsReport: 49ers have structure in position for Brandon Aiyuk patronize two teams San Francisco ChronicleReport: 49ers have worked out platforms of Brandon Aiyuk patronizes Browns, Patriots 49ers Webzone49ers insider provides latest upgrade on Aiyuk as field gossips swirl Yahoo Sports.