The Philip Rivers era is over in Los Angeles, and the Justin Herbert era is yet to begin. Tyrod Taylor will bridge the gap, although the last time he was a bridge quarterback, his time did not last long. In any case, the Chargers still have a playoff-caliber roster that is strong in most areas. However, there is one glaring hole, and it was unnecessarily self-inflicted.

Mike Pouncey (center) and Dan Feeney (left guard) are both solid, and longtime Green Bay Packers right tackle Bryan Bulaga, one of the league's best at his position, was signed in free agency. Right guard Trai Turner has made five consecutive Pro Bowls, and was acquired via trade this offseason. Reinforcing the interior offensive line was smart.

The problem was that the Chargers traded left tackle Russell Okung for Turner. While Okung is not elite, he's been a more than serviceable tackle for a decade, although he has also struggled with injuries, missing 10 games last season.

Having a good left tackle is more valuable than a great right guard, and while Turner is solid, he's not great; the Pro Bowl has essentially become a popularity contest, and is no longer a good way to judge players. That said, Turner is an upgrade at his position. The question is whether the upgrade at guard is worth the downgrade at tackle.

The answer to that question is no. As of now, Trent Scott, Tyree St. Louis, Sam Tevi, Trey Pipkins, Storm Norton and Ryan Roberts are the other tackles on the roster.

Scott started nine games at left tackle last season, and played a total of 827 snaps, earning an overall grade of just 49.6 according to Pro Football Focus. Because of his experience (relative to the other contenders at least), Scott may be the favorite to start the 2020 campaign at left tackle. That's not great news for Chargers fans.

St. Louis was signed as undrafted free agent in 2019 by the New England Patriots, and has spent time on their practice squad, as well as that of the Indianapolis Colts' and the Chargers'. He has no regular season experience.

Tevi, a sixth-round pick in 2017, has been L.A.'s starting right tackle for the past two seasons, earning overall grades of 54.5 and 59.8, respectively. He does have experience, but it's bad experience.

Pipkins is perhaps the dark horse in the left tackle competition. He was a third-rounder last year (91st overall), and started three games while seeing action in 10 others. Coming out of Sioux Falls, he was seen as a developmental prospect, and played as such, earning a 63.3 overall grade. That is not terrible, however, and given the stage of his career he's in, likely has the most potential of all the current options.

Norton went undrafted in 2017 and has three career snaps, all coming on special teams. He played for the L.A. Wildcats of the XFL, and his 80.2 grade paced all of the league's offensive lineman. It's highly unlikely that level of play translates to the NFL, but he does have a solid shot at making the team.

Roberts is a UDFA out of Florida State, was a member of a poor offensive line in college and has an uphill battle to earn an NFL roster spot.

It's clear that the left tackle position is not in good shape. However, there are multiple free agents who just make too much sense for the Chargers to sign, it's puzzling none of them have been added yet.

Cordy Glenn has played for the Buffalo Bills and Cincinnati Bengals, and is an above-average player. He will be 31 years old in September and has been injury-prone over the past four seasons. But if healthy, he would provide a significant upgrade at left tackle.

Kelvin Beachum has been a very good pass protector for the past seven years and spent the past three seasons with the New York Jets. He missed three games in 2019, but, like Glenn, he presents an excellent option to protect Taylor's blindside.

While Glenn and Beachum are great options, Jason Peters is even better. A former tight end, Peters is still a terrific player at the age of 38. He's been an elite pass protector for his entire 16-year career, and is still a quality athlete. The Philadelphia Eagles decided to not bring back Peters in order to give 2019 first-rounder Andre Dillard the left tackle job. Peters can still provide top-tier protection for a playoff team, and it's hard to find a better fit than the Chargers.

There's still time for the Chargers to upgrade at left tackle, but if they haven't done it yet, it's unlikely they'll do it at all. If the status quo doesn't change, Herbert may be starting sooner than intended.