Keenan Allen looks fit while catching passes during Chargers drills

With the Chargers veterans and rookie class taking the field for the first time together Tuesday, coach Anthony Lynn and the team would get to see their first-round pick, Mike Williams, catch passes from quarterback Philip Rivers.

That, thanks to some soreness in Williams’ lower back, didn’t happen.

“Right now, it’s the offseason,” Lynn said. “We don’t play anyone next week. So, we’re taking our time with Mike.”

But Rivers had another option to target during the team’s first organized team activity (OTA). Keenan Allen, who hasn’t been on the field since the opening game on last season’s schedule, made a surprise return to full-team drills.

“I actually didn’t think I’d be out here competing like this,” Allen said.

Allen’s first practice since tearing a ligament in his right knee in September went well, with the fifth-year receiver and Rivers connecting on passes in seven-on-seven and 11-on-11 drills.

“We’ve been real cautious with him. We’re just working him in right now on a limited basis. He’s full go,” Lynn said of Allen. “…He’s been running well. He’s been running routes well. And, he’s done a hell of a job in the training room.”

Allen originally thought he wouldn’t be healthy in time to participate in any of the OTAs, never mind the first one of the summer. Training camps seemed like a safer bet for Allen’s return.

But Tuesday, Allen looked like his old self, save for the bulky knee brace. He was able to run routes at full speed, digging his right foot into the turf before cutting and sprinting.

Those dynamic movements, the ones that have helped Allen catch 221 passes in his NFL career, were the final hurdles he needed to clear to get back on the field.

“[It was] confidence to put major pressure on the right leg and do what I wanted to do with it,” Allen said. “Anytime I can run a route without thinking about my knee … definitely confidence.”

Lynn thinks it’s important for Allen to take those steps now instead of in July when the team begins training camp.

“In training camp, we’re getting ready for Week 1,” Lynn said.

Eventually, Williams will be on the field. Travis Benjamin will return from injury too. Added with receivers Allen and Dontrelle Inman, tight ends Hunter Henry and Antonio Gates, and running back Melvin Gordon, the Chargers offense seems stacked.

“It’s going to be major, man,” Allen said. “Us together with everybody, who knows the limit? I feel like we have so many threats, so many weapons that we can use.”

Notes

Lynn, who has spent his pro football career on offense, said he’s focused on doing some tourism during the OTAs. “Right now, I’m spending most of my time with the defense, learning some things and how they’re doing it and how they’re communicating,” Lynn said. “I’ve been on the offensive side of the ball all my life. This is an opportunity for me to learn defense, which will make me better on offense.” … The Chargers didn’t use any of their rookies with the first-unit offensive line Tuesday. …Cornerback Casey Heyward left practice early because of a left ankle injury, though Lynn said it wasn’t a big deal. … The Chargers signed undrafted free-agent Mitchell Paige and waived linebacker Carlos Fields. Paige tried out for the team during their rookie minicamp over the weekend. … Longtime NFL assistant coach Rob Ryan observed practice from the sidelines.

daniel.woike@latimes.com

Twitter: DanWoikeSports