Young receivers could challenge ex-Steeler in battle for roster spot
Ateman, at 6-foot-4, could be a threat to beat out other wideouts such as Roberts, Holton and Switzer
Irvin has stayed in contact with his teammate and says he's working hard
Gruden and Carr, however, will likely be the biggest stories of the summer
Gruden is eager to get started on Year 1 of his deal, with the opening of training camp this week
