CLEVELAND — The preseason may have been virtually meaningless for the Browns’ starting offense and defense.

But Games 3 and 4, the latter Thursday night against the Detroit Lions at FirstEnergy Stadium, illustrated one glaring fact. The Browns might need one more draft and free-agency offseason to build the depth required to win the Super Bowl.

General Manager John Dorsey and his staff could be busy this weekend making waiver claims to shore up the bottom of the roster. The fifth and possibly sixth receivers who survive Saturday’s 4 p.m. final cut might not be Browns when practice begins next week for the Sept. 8 opener against the Tennessee Titans. That’s also true of the backups at tight end, running back and offensive line.

It was no surprise that Dorsey traded for a possible replacement for right guard Eric Kush on Thursday, acquiring Wyatt Teller from the Buffalo Bills in exchange for fifth- and sixth-round picks in the 2020 draft. Dorsey could also be looking for a tackle, although the New England Patriots got a head start on that by trading for two offensive linemen, including one tackle, on Wednesday.

As the preseason concluded, the excitement over an offense led by quarterback Baker Mayfield, receivers Odell Beckham Jr. and Jarvis Landry and running back Nick Chubb has obscured the Browns’ weaknesses.

Starting tight end David Njoku may have a physique not seen in Cleveland since the heyday of linebacker Chip Banks in the 1980s, but Njoku’s pass catching is erratic. Last season, he recorded a career-high 56 receptions and four touchdowns, but on 83 targets.

Many elite NFL offenses have a Pro Bowl-caliber tight end and Dorsey’s offseason challenges of Njoku may not make him one. Finding a quality backup from the likes of Demetrius Harris, Seth DeValve (also working at fullback), Pharaoh Brown and Rico Gathers (who played college basketball at Baylor) is also a stretch.

The Game 3 loss at Tampa Bay on Aug. 23 showcased the inadequacies of the back end of the receiving corps, with Jaelen Strong and Derrick Willies unable to pull in passes. Strong was waived Tuesday, opening the door for former Ohio State quarterback/receiver Braxton Miller, who was signed on Aug. 21 after spending last season on the Philadelphia Eagles’ practice squad.

Compounding the issue is that the Browns will be without No. 3 receiver Antonio Callaway for the first four games, suspended for an NFL substance abuse violation. That pushed Rashard Higgins, who built chemistry with Mayfield in last year’s training camp, into Callaway’s spot behind Beckham and Landry, but left few others to count on, along with a notable lack of speed.

Alliance of American Football product Ishmael Hyman didn’t help himself in the first quarter against the Lions, failing to catch three consecutive passes, the first a blatant drop on a Garrett Gilbert bomb. The loudest cheers of the yawn-worthy first half came on catches by Miller, a 36-yarder by Willies and a 7-yard TD catch by running back Dontrell Hilliard.

Even after the Teller trade, the Browns’ offensive line remains a major cause for concern. Left tackle Greg Robinson bailed out the Browns in starting the final eight games of 2018, but he’s on a one-year prove-it contract. The right side brings major question marks when it comes to keeping Mayfield upright. With the uncertainty of presumably Teller and right tackle Chris Hubbard, opponents will send the pressure right at them.

If left guard Joel Bitonio or center JC Tretter were to miss regular-season time, the lack of quality backups will be magnified. Guard/center Austin Corbett, a second-round pick in 2018, looks to be the biggest whiff of the GM’s tenure. There was a reason Corbett was trending on Twitter in Ohio on Thursday.

The Browns must fortify the line because Mayfield’s health — and the season’s success — hangs in the balance. A Super Bowl victory? That may require bolstering depth with a couple more Dorsey discoveries, which could be months away.

Marla Ridenour can be reached at mridenour@thebeaconjournal.com. Read the Browns blog at www.ohio.com/browns. Follow her on Twitter at www.twitter.com/MRidenourABJ.