Johnson was widely considered a 4th or 5th round talent, yet fell to Buffalo in the 7th round at the 224th overall selection.
Terms of Johnson's contract were not disclosed per team policy. The Bills have now signed each of its three seventh round picks, having previously locked up cornerback Kennard Cox and linebacker Demetrius Bell.
With the Wildcats at college, Johnson was only the fourth ever WR in school history to gain at least 1,000 yards receiving in one season. The wideout logged 1,041 yards his senior year and caught 13 touchdowns - one shy of Kentucky's single-season record.
Johnson made plenty of plays during Buffalo's OTA segments.
"He's doing a good job," Bills wide receivers coach Tyke Tolbert said . "He's like all the other rookies, the head's spinning a little bit. But he's a playmaking guy. We were very fortunate to get him where we drafted him because we had a higher grade than where we got him."
Said Johnson: "The seventh round seems like a free agent so of course I feel I have to make any play because there's no room for mistakes or anything," said Johnson. "So there's pressure, but it's no different than college or high school."
Johnson's NFL career got off to a rough start on Buffalo's bar strip in late May. The wideout was the passenger in Marshawn Lynch's hit-and-run fiasco.
But give this guy a shot. Johnson is in a great situation and has the talent to surprise some folks. At 6-foot-2, 202 pounds, Johnson is one of Buffalo's bigger wide receivers. At Kentucky he had a penchant for making the big play. Three of his touchdowns were game-winners in Kentucky's surprise season - including the GW TD against the national-champion LSU Tigers.
Johnson must make some plays in Buffalo's preseason schedule to dart himself on the map. Seventh-rounders usually have less than a 50/50 shot at cracking the 53-man roster it seems. But considering the Bills' shaky crop of receivers and Johnson's collegiate success in the most brutal conference, he'll certainly get a long look this summer.
Stay tuned to the BFR for more draft picking signings as they happen.