INGLEWOOD, Calif. -- The Chargers offense picked up their first down of the game on Saturday evening at 5:01 left in the second quarter during their 16-3 loss to the Seattle Seahawks.

At one point, the Chargers had a total of 15 yards, and the Seahawks had 125 yards.

"Offensively, we underperformed," Harbaugh said.

It was an ugly offensive performance, to say the least, but it has to worry head coach Jim Harbaugh and offensive coordinator Greg Roman.

There is a possibility they could not have starting quarterback Justin Herbert for week one against the Las Vegas Raiders. 

Herbert is still in a walking boot after a plantar fascia injury over a week ago. The team said in a statement that he would be reevaluated after two weeks and eased back into it.

Easton Stick is currently the backup, but his performances during training camp, when he took over for Herbert, and against the Seahawks show that Harbaugh and GM Joe Hortiz should start window-shopping.

Stick played the first half, throwing for 31 yards, completing five passes in 13 tries, and had one interception.

"Frustrating, obviously," Stick said. "A bunch of three-and-outs and turnovers. So, yeah, frustrating."

The interception came with 13:27 left in the second quarter, the Seahawks had just scored a touchdown when Stick threw it too high for tight end Hayden Hurst and right into the hands of Coby Bryant. Hurst took a hard hit, got up, hobbled, and didn't return to the game.

Two drives later, Stick faced third-and-four on his 26-yard line when he decided to throw left to rookie receiver Brenden Rice, who was tripled covered. On the other side, he had Quentin Johnston one-on-one against the Seahawks cornerback.

Stick was also sacked twice, but the offense had no flow. They mustered only nine first downs, 198 total yards, two third-down conversions and three points.

"Go through video and learn and grow, I think personally and as an offense," Stick said. "We'll jump into that and see."

He played in four games last season when Herbert's season ended abruptly due to a right index finger injury.

The Raiders blew out the Chargers at his first start, which wasn't his fault because Brandon Staley's ship was sunk. In the following three weeks, the offense scored one touchdown on a Stick touchdown run against Buffalo. Cameron Dicker kicked 13 field goals in the three games, making 12 of them.

There hasn't been a huge jump in his game.

Since Herbert's injury in camp, the offense has lost its juice. They played poorly against the Rams in joint practice and fail to move the ball consistently.

"Timing, blocking in the run game," Harbaugh said on what they need to improve. "Zone blocking, the gap blocking. The timing in the passing game. The protection — good at times, other times we missed or one guy got beat or more on a play. It was pretty wide spread, but you go back and attack it."

It would be unfair to compare any backup to Herbert. He isn't Herbert. Herbert is unique. The backup should be able to jump in and win a game if need be, and the Chargers don't have that in their quarterback room.

Max Duggan and Luis Perez performed better than Stick, but it was a different scenario, especially since the Seahawks were playing a lot of starters on defense.

The only available veteran is Ryan Tannehill, but if not him, the Chargers should look around the league. They faced PJ Walker on Saturday, and he is QB3 right now for the Seahawks. The Browns have Deshaun Watson, Jameis Winston, Tyler Huntley, and Dorian Thompson-Robinson in camp. They aren't keeping all four. 

It is time to work the phones and find a backup.

"Anything is possible," Harbaugh said about trying outside options. "Top of mind right now is getting on this film, and there's several things to attack, and that's what we're about doing."

Players who stood out:

Chargers defensive coordinator Jesse Minter said Wednesday he was excited to see edge rusher Tre'Mon Morris-Brash. The rookie out of Central Florida produced a highlight right away when he went past McClendon Curtis and hit the arm of Sam Howell to bring up 4th down.

Edge rusher Tuli Tuipulotu had multiple good rushes during the game and came up with three tackles. He is going to be a player to watch this season.

Linebacker Nick Neimann has been having a strong camp, which he continued on Saturday. He had 11 tackles, one sack, and a tackle for loss. The linebacker has been a key player on special teams and has made an impact on the defensive end.

Linebacker Troy Dye and undrafted safety Thomas Harper had sacks in the game. Harper made some plays during camp and a good one on Saturday.