The Bengals defensive line, viewed as probably the deepest position on the club, has already taken some hits even before taking the field.

Two days after tackle Ryan Glasgow failed his physical, NFL media reported Friday morning that nose tackle Josh Tupou became the first Bengal to opt out of the 2020 season because of Covid-19. He'll receive a stipend that will be taken out of his $1.2 million salary next season.

That leaves the Bengals without their back-up nose behind free-agent pickup D.J. Reader and figures to put them in the market for a veteran to replace some very valuable snaps. Profootballfocus.com rated Tupou as the 25th best tackle against the run after he played 44 percent of the downs and he would have been paired with Reader, rated the sixth best against the run. The 6-3, 345-pound Tupou, 26, a 2017 college free agent out of Colorado, has proven to be difficult to move and was ranked No. 32 overall among tackles by PFF.

They now need to get more from last year's fourth-round project Renell Wren, a massive 6-5, 320 pounder whom battled injuries during his rookie season. And they think they can because they're high on his athleticism despite his size.

But they also need to fill the cupboard with experience. The only other pure nose man besides Wren appears to be college free agent Trey Dishon out of Kansas State. Glasgow, who played just eight games the past two seasons after injuring the same knee, is more of a three technique. It's a spot played by three-year vet Andrew Brown as well as college free agent Tyler Clark.

Isaiah Prince, a second-year tackle from Ohio State, also decided to opt out. A sixth-round pick by Miami last season, Prince didn't arrive in Cincinnati until December via waivers and didn't get in a game. The Bengals still have depth at tackle with starters Jonah Williams and Bobby Hart, swingman Fred Johnson and sixth-rounder Hakeem Adenij, as well as O'Shea Dugas, a rookie last year that spent the season on injured reserve.