The Pittsburgh Steelers are expected to have the best defensive line in the NFL heading into the 2021 season.

Pro Football Focus ranked the Steelers as the No. 1 defensive line in its league wide ranking of the position group.

Given that the Steelers use a 3-4 defense, outside linebackers were included as edge defenders in the rankings.

The Steelers topped the list despite being "slated to take a step back after replacing Bud Dupree with Alex Highsmith," but -- like head coach Mike Tomlin -- the website expects Highsmith to have a breakout season in 2021 playing among an already dominant unit.

"Highsmith finished his rookie season with a higher pass-rush win rate (16.5%) than Dupree (13.7%) last year. He joins a group that already features T.J. Watt, Cam Heyward, Stephon Tuitt, and Tyson Alualu, all of whom made PFF’s list of the top 32 players at their respective positions entering the 2021 NFL season. That group will look to match a league-leading 45.1% pressure rate in 2020.

As a rookie, Highsmith started five games in the absence of Dupree, who experienced a season-ending ALC tear in December.

In April, Tomlin not only confirmed that Highsmith will continue to serve as the Steelers' starting outside linebacker amid Dupree's decision to sign with the Tennessee Titans as a free agent this offseason, but also credited his "natural maturation" during a pre-draft press conference alongside general manager Kevin Colbert.

"In regards to the loss of Bud and the expectations and the depth and things at that position, the lynchpin to that entire discussion is the natural maturation of Alex Highsmith from Year 1 to Year 2,” Tomlin said. “You know the standard of expectations that we have for our young players moving from [Year] 1 to [Year] 2. He could be the poster boy for that. We need a significant rise in terms of all areas of play from him. But I also think it’s reasonable to expect it given what he’s been exposed to, given the quality young man that he is and his work ethic and the environment we intend to put him in. I think it’s reasonable to expect him to rise up and meet the challenges.”

Highsmith appeared in all 16 games during his rookie season, recording 48 total tackles, 2.0 sacks, five tackle for loss and six QB hits in 2020.

Watt is coming off yet another dominant season in which he was a finalist for the 2020 NFL Defensive Player of the Year Award won by Pittsburgh native and former University of Pitt standout Aaron Donald.

Watt earned a 91.6 overall grade from Pro Football Focus after leading the NFL in sacks (15) and tackles for loss (26), while also recording 53 tackles, one interception, two forced fumbles and 41 QB hits.

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