Diggs did most of his work out of the slot in 2016 (43 catches, 478 yards) and shifted to a role outside last season whereas Thielen lined up inside more often than not (46 catches, 592 yards) in 2017 and caused mismatches with his speed.
He made 39 of his 94 deep-ball attempts (passes that traveled 20 or more air yards) for an NFL-best 1,359 yards, 11 touchdowns and three interceptions in 2016.
Regularly at the other end of those passes was Jackson, who averaged 17.9 yards per catch and became Cousins' favorite vertical threat.
There are a couple of areas to zero in on in determining how having Thielen and Diggs can take Cousins' game to the next level.
The first goes back to his bread and butter with Jackson: the deep ball.