It's the era of big boy receivers, and I'm all the way here for it. Ole Miss’ D.K. Metcalf, NC State’s Kelvin Harmon, Arizona State’s N’Keal Harry, and JJ Arcega-Whiteside are four absolute loads to handle for undersized corners due to their size, strength, and physicality.
Yet all but Metcalf have warranted concerns about their ability to separate from sticky man coverage. These concerns are born from a place of questionable technique and effort at times, but at other times come from a consideration of physical traits. To separate, it would seem, you need have great explosiveness; great change-of-direction; great long speed.
That simply isn't the case. Perhaps separation is too ambitiously named, but separating does not mean being entirely out of contact with the corner in question; completely shaking them into next week with a sick little juke at the top of the route. Separation could be more aptly described as generating a throwing window: creating the expected space for the ball to arrive.
That separation is conditional on a lot of things. Spacing with other routes, timing with the quarterback, and the design of the route itself. And accordingly, it can be created by a number of things: burst, long speed, quickness, physicality, good route-running, tenacity, and situational understanding.
That's why I don't have nearly as great of concerns as others do about JJ Arcega-Whiteside's ability to separate at the NFL level. His athletic testing still matters, and poor testing will lower his floor as a player -- but independent of what he runs and jumps in Indianapolis, I see a player on film who can generate throwing windows regularly with great route-running, situational understanding, and good burst.
He'll never uncover like a Tyreek Hill or shake-and-bake like a Doug Baldwin, but you shouldn't expect him too. By simply taking his film for what it is, you can see how Arcega-Whiteside can regularly create downfield throwing windows and warrant a high volume of deep targets at the next level.