The PFWA's version of the award is lesser-known than that given by the Associated Press. Those players selected by the AP -- including defensive rookie of the year -- will be announced at the NFL's annual award show on Feb. 1 in New York.
Alonso, selected in the second round, played every defensive snap this season. He finished with 159 tackles, third-most in the NFL.
Earlier this month, ESPN NFL draft analyst Mel Kiper Jr. named Alonso as his defensive rookie of the year. Also, Alonso becomes the first Bills rookie since linebacker Shane Conlan in 1987 to earn AP or PFWA rookie of the year honors.
The PFWA also released its All-NFL and All-AFC teams this week. No Bills made the cut.