EL SEGUNDO, Calif. -- Since quarterback Justin Herbert entered the NFL and became a starter in 2020, the Los Angeles Chargers' success has largely depended on how well he played.

This led to Herbert having the highest passing attempts per game in NFL history heading into this season (39.1) and breaking many records early in his career including passing Andrew Luck for the most passing yards (14,089) in a quarterback's first three seasons.

But the Chargers and Herbert don't have much to show for it. Herbert, now in year five, has led the Chargers to the playoffs once, in 2022 -- where they lost in historic fashion, blowing a 27-0 lead to the Jacksonville Jaguars in the wild-card round. It largely explains why Herbert has had three head coaches and four offensive coordinators in five seasons. The organization believes they have a quarterback good enough to contend, but they've struggled to find the right pieces to make the Chargers consistently competitive.

Ownership was hopeful that coach Jim Harbaugh would be the leader that would give Herbert and the Chargers (at Denver, Sunday, 4:05 p.m. ET) team success, but through five weeks, this team is in the same spot they were a season ago: 2-2. Only this time, however, the offense under offensive coordinator Greg Roman has relied less on Herbert, who has career lows in almost every category through four weeks.

"If we throw 500 times or 50 times, we just have to be executing as an offense," Herbert said. "Selfishly, I love to throw the football, but I want to get this offense to be as best as we can and what that looks like? It changes from week to week."

The Chargers finished last season 3-10 after splitting the first four games. As they look to avoid repeating that this season, it poses the question: Have the Chargers strayed too far from Herbert's strengths?

"I love it when Justin Herbert's back there and is able to throw the football. We all do. It's a thing of beauty, but we're trying to build something here that's sustainable," Roman said, "that can win in a lot of different conditions under different circumstances.

"So I think we want to have that balance, but there are definitely going to be some days where we're able to let Justin go to work throwing the football. Those days are coming again. We really haven't even scratched the surface."

Through the first four weeks, Herbert has the fewest passing yards (578), completions (59), and passing attempts (91) in any four-game span of his career. The drop-off was somewhat expected because of Roman's history, but Herbert's numbers are perhaps lower than even anticipated.

Roman, who was most recently the offensive coordinator with the Ravens in 2022, put together some of the most prolific rushing offenses in NFL history. His offense sparked quarterback Lamar Jackson to win the second unanimous MVP award in NFL history in 2019. That same season, Roman won the AP Assistant of the Year award.

But his scheme quickly soured in Baltimore. Players complained about play calling and someone placed "Fire Roman" fliers outside the team's facility entrance. He resigned after the 2022 season. Since he's arrived in L.A., Roman has been adamant that the Chargers offense will be balanced, but it hasn't been that way so far.

The Chargers have the second-highest designed run percentage in the league on first down (64%) and the third-highest rate on second downs, but the rushing offense hasn't been effective, averaging 3.9 yards per carry, the 23rd worst in the NFL.

Roman credits the unbalanced rushing and passing splits to the flow of the games they have played. He pointed to their rushing dominance through the first two weeks, where they led the NFL in rushing yards after wins over the Carolina Panthers and Las Vegas Raiders.

"When you look at the Carolina game, I mean, should we have thrown more there?" Roman asked rhetorically. The Chargers ran for 219 yards in that game. "It was working really well, so you kept doing it and then the numbers get skewed a little bit."

Roman also noted that his play calling has been limited because of a high right ankle sprain Herbert has nursed since Week 2 and injuries to the team's starting tackles, Joe Alt (MCL sprain) and Rashawn Salter (pectoral). "There's a lot of stuff we haven't even touched yet, haven't been able to put out on the field," he said.

Roman continued: "There's a couple of plays in that game last week where we probably would've gone in a different direction, you know what I mean? But that's the game."

The Chargers haven't been the sustainable offense that Roman and Harbaugh are striving to build yet this season, but neither is the Chargers offense of old. Herbert throwing nearly 40 passes per game didn't make the Chargers contenders.

As the season grows, they hope to reach a happy medium.

"I feel like it's close," Harbaugh said of the offense, "but with anything in life, just keep doing what we're doing but want to get a little bit better at something, work a little bit harder at it, that's where we're going."