It's no secret the Detroit Lions' coaching staff has been one of the keys to the franchise's turnaround over the past three years, culminating in its first division title in 30 years. Now the spotlight is focused on two coordinators not normally in the limelight: Aaron Glenn and Dave Fipp.

That duo was recognized by NFL players as two of the best at their respective jobs.

Glenn was voted as the best defensive coordinator and Fipp was voted as the fourth-best special teams coordinator in the NFL in a survey released by the NFL Players Association on Thursday.

The NFLPA conducted an anonymous survey of over 1,700 players between late August and mid-November about the top coordinators for each unit from around the league. The top five coordinators received the highest average rating from players on their respective teams in the survey, according to the NFLPA.

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The goal of releasing these results, according to a statement from the NFLPA, is to "highlight and focus on the positive impact coaches can have on players across the league" and "ensure that players' opinions are heard and accounted for by clubs ahead of the next hiring cycle."

Glenn received the highest rating for defensive coordinators, above Steve Wilks (49ers), Dan Quinn (Cowboys), Brian Flores (Vikings) and Raheem Morris (Rams). Fipp received the fourth-highest rating behind John Fassel (Cowboys), Chris Tabor (Panthers) and Matt Daniels (Vikings), and was ranked ahead of Darren Rizzi (Saints).

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In an interview with ESPN, NFLPA president JC Tretter said that Glenn was the highest-rated coordinator across offense, defense and special teams.

Glenn has received flak throughout his three-year tenure with the Lions because of up-and-down performances from his unit as the offense has morphed into one of the juggernauts of the league. The Lions ranked 31st in scoring defense (27.5 points allowed per game) in 2021 — Glenn's first year — and improved marginally to 29th last season (25.1 points allowed per game).

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The defense took another small step forward in scoring (23.4 points allowed per game) to rank 23rd while ranking 15th in total defense (329.1 yards allowed per game). Detroit has been stout against the run, giving up 88.8 yards on the ground per game, fifth-best in the league, but has struggled in the secondary giving up an average of 240.4 passing yards per game, 25th in the NFL.

The defense has had to deal with injuries for most of the season, but is getting healthy at the right time before the playoffs begin. Glenn is working on a new rotation at safety with the return of C.J. Gardner-Johnson and defensive linemen Alim McNeil and James Houston are nearing a return from their respective injuries.

This article originally appeared on Detroit Free Press: Detroit Lions' Aaron Glenn voted as NFL's top DC in player survey