When the offseason began, the Cleveland Browns boasted the best interior offensive line in the NFL. Left guard Joel Bitonio, center J.C. Tretter, and right guard Kevin Zeitler protected quarterback Baker Mayfield, as the Browns gave up only nine QB hits over the final eight games of the 2018 season.

But Zeitler was traded to the New York Giants for pass rusher Olivier Vernon. A significant upgrade on the defensive side of the ball, but the loss of Zeitler was a bigger deal than most people thought at the time of the trade. Zeitler is a bona fide elite player, and now, over five months later, the Browns still don't know who is going to be replacing him.

The first option was second-year player Austin Corbett, the first pick of the second round in 2018 who spent his rookie season on the bench. The thought process behind his selection was… interesting to say the least.

Corbett played left tackle at Nevada, but due to his 33 1/8″ arms was considered to be a guard convert in the NFL. Cleveland chose him over plenty of other good OL prospects (Will Hernandez, Braden Smith, Connor Williams, and James Daniels) because they thought he might have a chance at remaining at LT, starting right away and filling the void left by the retired Joe Thomas. And if that didn't happen, he would be a good guard when the time came for him to play.

That plan was abandoned quickly, as after a few practices, Corbett was shifted inside to guard, and Bitonio was moved outside to LT, a decision that was labeled as “Plan Z” by the coaches just weeks before it happened. This lineup didn't look bad in the preseason, but once rookie undrafted free agent Desmond Harrison was able to practice after missing training camp and half of the preseason, he was inserted at LT and Bitonio moved back to LG, forcing Corbett to the bench.

In hindsight, this is when questions should have been raised about Corbett, as Harrison was abysmal for the first eight weeks of the season before being inactive with an undisclosed illness while Greg Robinson took over his spot. If the coaching staff truly thought that Harrison/Bitonio were better than Bitonio/Corbett, how bad was the rookie during practice?

But no matter. That debacle can be dismissed as another Hue Jackson failure, and Corbett will be ready to go once he takes over at guard now that Zeitler is gone, right?

Although Corbett is still officially “in the running” for the starting right guard position, he hasn't practiced there in weeks, instead being relegated to the backup center spot. He's played that spot for nearly the entire game preseason so far, and after a decent showing against the Washington Redskins, put up a very poor performance against the Indianapolis Colts.

In fact, he wasn't even the first center to take over for Tretter; that was Eric Kush, the current leader in the RG race. This may be an indication that the coaching staff is not totally confident in Corbett being the backup there.

Corbett had multiple bad snaps, including this one. Yes, he's rather inexperienced at center, but that isn't an excuse. Kush didn't have any bad snaps while he was playing there, and he practices exclusively as a guard. Corbett practices only as a center now.

This is another bad rep from Corbett. His man doesn't even make the play, but he would have if multiple Colts hadn't gotten penetration. This is a run play, meaning that Corbett can explode out of his stance and drive his man back, not having to worry about dropping into a pass set.

But Corbett is immediately blown back two yards, and the defender gets outside leverage as he is running towards the sideline. Whether this is a lack of strength or lack of aggressiveness is unknown, but Corbett isn't known to have a mean streak, at least not to this point.

Here, Corbett is confused by the stunt attempt, but at least recovers enough to get in front of the defender. But he then overcommits and is easily disposed of by a simple swim move and gives up the sack.

Where to start with this one? First, Corbett delivers a high snap, causing QB David Blough to abandon the pass and scramble upfield. Then, his man wins immediately, forcing Blough out of the pocket and nearly getting a sack. And on top of all that, Corbett gets called for a holding penalty. Absolutely brutal. No.76 is Sterling Shippy, an undrafted free agent out of Alcorn State. The starters have long exited the game, and Corbett is still struggling mightily. Not a good look.

Kush has been average in the preseason thus far, and has played more than any of the other starters, since he has yet to completely claim the first-string role. Ironically, Kush lost his spot with the Chicago Bears as a result of James Daniels, drafted shortly after Corbett.

Kush was able to manage both Denico Autry and Margus Hunt with little issue, although Hunt did get some good push on this play:

He doesn't have to be as good as Zeitler. That's never going to happen. But Kush does have to be solid. In 2018, he was a very effective pass blocker, but played only 218 pass snaps. Compare that with Zeitler, who played 694 pass snaps and graded out around 11 points higher according to Pro Football Focus. Kush must prove that his small sample size of good play was not a fluke. So far this preseason, he has been unable to do that.

Rookie sixth-round pick Drew Forbes has developed quickly and has earned himself first-team reps in practice and plenty of playing time in games. The physical tools are there with Forbes, but he is a tackle convert from a small school, so the mental aspect of the game is going to be a work in progress for him. He probably won't end up starting this season, but has a chance to be a long-time starter in Cleveland with more development.

The best thing about Forbes is his athleticism. He is noticeably quicker and more fluid than any of the Browns other offensive lineman. Here, he easily pulls around the line and engages the CB to open up a massive hole for the RB.

On this play, Forbes absorbs the bull rush well and is able to anchor, but by the time he does, the QB would have been hurried had he not already been scrambling due to the high snap.

Then on Monday, a new competitor entered the ring. Kendall Lamm is a swing tackle by trade, and was signed away from the Houston Texans this offseason. He was given some first-team reps at guard, which further clouds the situation.

Even ignoring the disappointment that Corbett is turning out to be, all the Browns needed was for one player, any player, to take control of the right guard spot, and none of them have. Quarterbacks, especially shorter ones, need strong interior pass blocking. They need to feel comfortable standing in the pocket and moving up in it, not paranoid that a blocker is going to come straight up the middle, forcing them to drift back and outside, which makes it easier for edge rushers to get home.

Yes, the defense is going to benefit greatly from the addition of Vernon, but the offense is going to miss Zeitler dearly. Right guard is 100% the biggest problem on Cleveland's roster, and there's no easy solution at this point. If it wasn't evident before, it is now; right guard is a problem for the Browns.