SANTA CLARA >> Christian McCaffrey, sporting a backward ballcap, sprang through traffic at the line of scrimmage and raced through the 49ers’ retooled defense. Top draft pick Mykel Williams, a defensive end, hustled in pursuit 20 yards downfield to draw praise from his coach.

That is how Thursday’s organized team activities fittingly ended: blending a holdover superstar amid the encouraging sight of a young prospect.

This was the 49ers’ first full-team practice — with a very new-looking squad — open to the media since last season left a 6-11, last-place finish.

And it had been six months since McCaffrey was last seen in action during his injury-shortened season, though he’s been present since the start of the offseason program in April.

For all the new arrivals looking to fill vast voids, it’s impossible to overlook the return of the 49ers’ marquee offensive weapon, all due respect to the steady sights of Brock Purdy and George Kittle fresh off signing contract extensions. The 49ers should be ecstatic that McCaffrey is running at full speed and without visible pain, albeit with no tackling or full contact permitted.

He is not among the injured players deemed out until training camp, a group including wide receiver Ricky Pearsall (hamstring) and safety Ji’Ayir Brown (ankle). Left tackle Trent Williams is the only veteran star not present, as he’s working out at his Houston gym before an expected arrival at mandatory minicamp in two weeks.

“Right now he’s as healthy as can be,” coach Kyle Shanahan said of McCaffrey. “We have to protect him from himself. But Christian has a good idea of what he needs to do right now.

“He’s doing a lot less than he normally would do,” Shanahan added. “I know he’s excited about as healthy as he is and he’s happy to get out there.”

McCaffrey bypassed last year’s voluntary workouts, signed a two-year extension at June’s mandatory minicamp, then, once the season arrived, missed the first two months because of Achilles tendinitis. In his fourth game back, he injured his right knee’s posterior cruciate ligament in the Buffalo snow just as he neared his old form.

McCaffrey got four touches Thursday — an early reception against linebacker Dee Winters, followed by three runs up the middle — during the hour of team drills, with no helmets allowed during the 11-on-11 work.

“Having Christian out there is awesome and he’s still really, really good at running the football,” said Kittle, noting that McCaffrey has spoken up and been engaged in team activities as an emerging leader.

Kittle also reminded everyone that McCaffrey is only a year removed from being the NFL Offensive Player of the Year. He vowed to be fully cleared by these OTAs, and he indeed looks ready to rejuvenate a franchise in great need of such a lift.

Notes

• Purdy looked comfortably in command of the offense and didn’t break from his usual, even-keel ways nearly two weeks after landing his six-year, $265 million extension. Shanahan said that contract stopped being a point of discussion after its May 16 agreement. “We were out of town so I called him from a boat to congratulate him, and we messed around a couple of minutes,” Shanahan said. “I haven’t talked to him about it since. When I see him in person, it’s not something we think about. ... I want him to be the leader he’s always been. There’s no worse thing than to ask someone to do something extra because of a contract.”

• Spencer Burford, formerly a starting right guard, and Austen Pleasants worked at left tackle in place of Williams. Ben Bartch was inserted at left guard in place of Aaron Banks, who signed with the Green Bay Packers in free agency.