Fantasy Upside
As Bleacher Report noted, at 5-foot-10, 160 pounds, Nelson does one thing well: Run fast. He's a deep threat who can occasionally beat defenders downfield. Thanks to that speed, Nelson is useful in keeping opposing defensive coordinators honest, pushing safeties back and opening the field up for teammates like Larry Fitzgerald and David Johnson. It will be up to new offensive coordinator Mike McCoy, who history tells us is a pass-heavy playcaller, to find ways to incorporate Nelson into the offense beyond being just a threat.
Fantasy Downside
Also per B/R, Nelson "has some of the worst hands in the league, and that often leads to devastating drops. He is a major liability as a blocker and can't run a full route tree."
2018 Bottom Line
Barring some kind of surprising revelations in training camp and during exhibition play, it's going to be hard for fantasy managers to justify an investment of draft capital in Nelson, or the team's other wideouts not named Larry Fitzgerald.