Receiver Mike Thomas boosts playing chances in Rams’ new offense

For the first time since training camp began, Mike Thomas on Monday ran routes and caught passes with other receivers.

The second-year pro showed the speed that boosts his chances of contributing to the Rams’ new offense, and he said he was happy to be back on the field with teammates.

But Thomas, who had been sidelined because of a foot injury, will sit out the first four games of the regular season because of a suspension for violating the NFL’s policy on performance-enhancing substances. The suspension was announced in July, about two weeks before training camp began.

“I just knew it was coming so I had to take full responsibility of it and learn from my mistakes and move forward,” Thomas said.

Thomas declined to specify the circumstances that led to his suspension.

“I don’t want to talk about it because it’s in the past already,” he said. “Just got to watch what I take and be more responsible and be more observant and just learn from it.”

Thomas’ return to the field gives quarterback Jared Goff a potential deep threat, at least for practices and exhibition games.

Tavon Austin and rookie Josh Reynolds, also regarded as potential deep threats, remain sidelined because of injuries.

“You feel that vertical speed that he has,” coach Sean McVay said of Thomas, a sixth-round draft pick last year. “That gives us a nice option, an element in our pass game and looking forward to just kind of progressing and building with him as we move towards the season.”

McVay said Thomas would play in exhibition games even though he will sit out regular-season games against the Indianapolis Colts, Washington Redskins, San Francisco 49ers and Dallas Cowboys.

“You still want to get him that work knowing that he’s a part of our plans for the season if things go the way that we anticipate and getting him back Week 5,” McVay said. “So, it’s a delicate balance of making sure that he gets the work that he can, but you’re also mindful that you’re not going to have him for the first part of the season.”

Thomas caught only three passes and was a standout on special teams last season.

After he was cited, Thomas said he was worried about his status with the Rams. But he impressed McVay during offseason organized team activities workouts and minicamps.

“In OTAs, I knew I was still going through this thing, I just never let it get to me,” he said. “I still made plays during OTAs.

“I just couldn’t let it get to me mentally because … negative stuff is going to build on each other and then I was just going to overthink stuff and lose my mind.”

Thomas said it was “very disappointing” that he won’t be able to help or be around the team in the first four regular-season games.

“I’m going to just keep working like it’s another offseason for me, those four weeks, and when I come back just get ready to work when my number is called and make plays,” he said.

Etc.

The Rams waived receiver Bradley Marquez, who caught 16 passes and played on special teams the last two seasons. Marquez had not practiced recently because of a knee injury. … The Rams practiced in full pads. … Goff connected with rookie receiver Cooper Kupp on a 25-yard touchdown pass to the back corner of the end zone. … Backup quarterback Sean Mannion read a blitz and connected with running back De’Mard Llorens. … Defensive back Aarion Penton intercepted a Mannion pass. … Tight end Travis Wilson continues to make plays, making a catch in tight coverage on a pass from Dan Orlovsky. … Safety Cody Davis broke up a few plays and narrowly missed intercepting two passes. … Actor Ty Burrell of the television show “Modern Family” attended practice. … The Rams are off Tuesday. They will hold a joint practice with the Chargers on Wednesday at 4:30 p.m. at UC Irvine. The workout is open to the public.

gary.klein@latimes.com

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