The term is often used when it comes to football personnel -- "We need a No. 1."
Matt Williamson of ESPN.com's Insider team attempts to quantify exactly what that means, listing out his criteria for what makes a true No. 1 pass-catcher. Considering a formula of getting open, having the necessary strength and size, productivity and consistency, Williamson then ranks his top "No. 1" pass-catchers in the NFL.
Patriots tight end Rob Gronkowski is trumped by only one player -- and he's in Detroit.
"If healthy, Gronk is the perfect tight end, and frankly, he could be the most impressive tight end who has ever played this game," Williamson writes.
Williamson's piece sparks thoughts about Gronkowski and how the Patriots' offense takes on a different look when he's on the field. It also shines a brighter spotlight on the team's tight end personnel, which currently includes Gronkowski, Michael Hoomanawanui and D.J. Williams. It's possible bigger receiver Mark Harrison could also be included in the mix.
While the Patriots have been active in free agency and appear to have improved overall, the greatest improvement might simply be Gronkowski's return to the field, whenever that may be.