Add J.C. Jackson’s pass-interference penalty late in the first half, and Sunday was a rocky return for the Chargers cornerback.

On Wednesday, in his first public comments since his team’s season-opening 36-34 loss to Miami, Jackson took responsibility for his most glaring error, the 30-yard, second-quarter infraction that allowed the Dolphins to kick a field goal with no time left.

After Miami took over at its 25-yard line nine seconds before halftime, its lone chance to score before the break required a major Chargers miscue.

Quarterback Tua Tagovailoa connected with receiver Jaylen Waddle for 22 yards and then launched a desperate heave into the middle of the field in the area of the Chargers’ 20-yard line as time expired.

Jackson used both hands to shove Dolphins receiver Erik Ezukanma in the back, resulting in the penalty. Miami’s Jason Sanders booted a 41-yard field goal and, instead of being tied at the half, the Chargers trailed 20-17.

“That was a bad mistake by me,” Jackson said. “I’ll take full blame for that. I should have been paying attention to the clock and everything around. I was just playing football.

“But I gotta know. … Coach is always talking about situational football. I gotta know what situation we was in. It’s me [paying] more attention to details going into the game.”

Jackson was playing for the first time since suffering a season-ending ruptured patellar tendon in Week 7 last fall. He had surgery and spent the offseason rehabilitating to the point where he was available for the start of training camp.

Coming back against Miami and speedy receivers Tyreek Hill and Waddle wasn’t ideal for Jackson, but that’s the schedule the Chargers were given. He played 44 of the team’s 67 defensive snaps.

Jackson said he’s still not 100% and, with the severity of the injury he suffered, there’s no guarantee he’ll regain the form that allowed him to be a Pro Bowler in 2021 with New England.

But on Wednesday, Jackson continued to express optimism about where he’s headed, repeatedly saying he’s “working” back to 100%.

“It’s a long season, man,” he said. “That’s Week 1. We’ve got a whole season ahead of us. That’s what I’m looking for. My goal is trying to stay healthy throughout the whole season.”

Jackson did have his first interception as a Charger, picking off Tagovailoa in the end zone in the third quarter. But on the Dolphins’ next offensive snap, Hill flew past Jackson for a 35-yard touchdown.

Coach Brandon Staley explained that Jackson was beaten on the play because of improper leverage. Jackson allowed Hill to streak past him on the outside when his help — in this case safety Derwin James Jr. — was inside.

“Mentally, I feel like he’s doing well,” James said of Jackson. “I feel like he’s going to respond. I told him, ‘Don’t keep your head down. We’ve still got your back. It’s one game.’ ”

Jackson struggled on a day when the Chargers’ pass coverage was historically bad. Tagovailoa finished with 466 yards, the most given up by a Chargers defense.

As unsightly as the performance was, Jackson took a philosophical approach.

“Sometimes you have to lose to get where you’re going,” he said. “To have success you have to fail first. Maybe our team needed that. Maybe our team needed that loss to wake everybody up, humble everybody.

“We came in here and let Miami beat us in our own house. Come on. What we going to do, man. But I’m not on to Miami. I’m worried about Tennessee. It’s Week 2.”

The Chargers travel to play the Titans on Sunday.

Etc.

Three starters were missing Wednesday as edge rusher Joey Bosa, running back Austin Ekeler and linebacker Eric Kendricks didn’t practice. Bosa is dealing with a hamstring injury suffered Sunday. Ekeler (ankle) and Kendricks (hamstring) also were listed as out for personal reasons. Ekeler’s agent and friend, Cameron Weiss, died Sunday after a lengthy battle with cancer.