Linebacker Reuben Foster has been cleared for full-contact practices, but the 49ers’ other first-round draft pick, Stanford defensive lineman Solomon Thomas, remained unsigned on the team’s first day of training camp.

Thomas, who was selected third overall, is represented by the same agency, CAA, that represents 49ers guard Joshua Garnett and Chargers pass rusher Joey Bosa. Garnett, a former first-round pick, signed his rookie contract on the eve of training camp last year. Bosa, who like Thomas was taken at pick No. 3, didn’t sign until August 29th.

Bosa finished the season with 10 1/2 sacks and was named the NFL’s Defensive Rookie of the Year.

General manager John Lynch said he was optimistic a deal would be completed soon and that the two sides continue to talk. Still, it was the lone blemish as the 49ers reported to camp on Thursday. Every other player was on hand and there were no injuries that landed players on preseason injury lists on Thursday. The team still could add a player to those lists on Friday.

“I’m concerned right now,” Lynch said about a potential holdout. “I wish this were done. I think it should be done.”

While Thomas missed most of the spring practices because Stanford’s school year still was in session, Foster was held out of practices to protect his surgically repaired right shoulder.

Lynch got the message this week that the most recent tests on the shoulder showed that it had fully healed. Foster will participate in practice with no limitations, including when the 49ers first dress in full pads early next week.

“Excited is an understatement,” Lynch said when asked about Foster’s demeanor.

“He’s champing at the bit,” he said of the famously ferocious linebacker. “He told us we almost had to have a leash on him to keep him out of the (spring) drills.”

Coach Kyle Shanahan said he was pleased to see how Foster dealt with missing most of the May and June sessions. He said that players, especially rookies, who don’t get on the field tend to tune out the classroom element of practice. That wasn’t the case with Foster, who also stuck around in Santa Clara during the month-plus break between spring sessions and training camp.

“I think he’s in as good of a spot as he can be without having stepped on the field,” he said.

Foster will compete with veteran Malcolm Smith to be the team’s weak-side linebacker. Thomas is expected to compete at left defensive end, a spot where Tank Carradine and Ronald Blair lined up in the spring.

The skinny on Hyde – Running back Carlos Hyde said he weighed 228 pounds Thursday, the lightest he’s been since high school.

“I feel like I’m in the best shape of my life,” he said.

Hyde has been the team’s unquestioned starter the last two seasons but this year must hold off a number of challengers, including veteran Tim Hightower and good-looking rookies Joe Williams and Matt Breida.

Hyde drew a compliment on his physique from Lynch – “He looks tremendous,” the general manager said – and said his objective in 2017 was greater than winning a starting role.

“My goal is to be the No. 1 rushing running back in this league,” he said. “I feel like I have the best opportunity to do that now.”

Contract years – Several prominent 49ers, including Hyde and strong safety Eric Reid, are heading into the final year of their contracts. There has been no talk of extensions to this point because the 49ers want to see how those players function in the schemes they are using this year.

“We’re going to let things play out a little bit and see how they fit with what we do,” Lynch said.