Detroit Lions first-round pick, offensive lineman Frank Ragnow, is having a strong preseason and he continues to receive high grades from Pro Football Focus, including earning a class-leading run-blocking grade.

PFF’s Mark Chichester looked at the grades of all 32 first-round picks from the 2018 NFL Draft and discussed Ragnow’s success:

Up until last week, the former Arkansas star was one of only three rookie guards to play at least 30 pass-blocking snaps and not allow a single quarterback pressure, but that came to an end against the Buccaneers in Week 3, where Ragnow allowed a sack, a quarterback hit and two quarterback hurries on his 21 pass-blocking snaps. Pass-blocking aside, Ragnow has been a consistent force in the running game and through three preseason games, he’s produced a draft class leading run-blocking grade of 73.5.

The pressures given up by Ragnow came after the Lions coaching staff moved Ragnow to right guard — after playing on the left side all offseason — to matchup him up against six-time Pro Bowler and former All-Pro defensive tackle Gerald McCoy.

Despite the production allowed to McCoy, Ragnow has proved he belongs on the starting unit in Detroit and the fact that he is already capable of playing all three interior positions at an NFL level is encouraging for his developmental ceiling.