With Gronk retired, who is the No. 1 tight end in the NFL?

How do the Pats plan to replace Gronk? (0:44)

Mel Kiper Jr. predicts that the Patriots will draft Alabama TE Irv Smith Jr. as a replacement for Rob Gronkowski. (0:44)

PHOENIX -- Rob Gronkowski's retirement leaves a crater at tight end for the New England Patriots and the NFL.

As Patriots coach Bill Belichick said of Gronk in a team statement, "His elite combination of size, skill, intelligence, toughness and ability to perform in pressure situations set him apart."

With top decision-makers gathering for the recent league meetings in Arizona, I asked four head coaches and four personnel evaluators to name the NFL's best tight end now that Gronk is vacating his throne. They were unanimous in their answer -- and in their belief that no current tight end approaches Gronkowski for all-around excellence.