COSTA MESA, Calif. -- Soon after Joe Staley officially retired from the San Francisco 49ers, coach Kyle Shanahan made it clear that the door would always be open for Staley to make the leap into coaching.

Staley, who is still fresh off 13 standout NFL seasons has been in no hurry to make such a jump, preferring to spend time with his family.

That doesn't mean Staley isn't interested in revisiting Shanahan's invitation at some point. With the Niners spending time much closer to Staley's Southern California home practicing with the Los Angeles Chargers, Staley is getting a part-time taste of life as an NFL coach this week. He wasted no time making an impression when he joined the 49ers coaching staff for the first time on Wednesday.

"Yesterday was his first day working," Shanahan said, smiling. "It was our off day and he was so amped up he was kind of annoying us all day wanting to do more. But I'm pumped that he's here. He's passionate about football. He loves football. It will be nice to have him in the room. He's never been on this side before so he's probably going to be a little sensitive in realizing how not always nice with what we say behind closed doors but we'll see how he does. And I know he'll be opinionated. ... I hope he enjoys it."

After spending Wednesday in meetings with Shanahan and his staff, the trimmed-down Staley was on the practice field in 49ers gear, working with the offensive line and even serving as the "quarterback" taking snaps in the one-on-one pass rush drills between the Niners' offensive line and Chargers' defensive line.

The plan is for Staley to spend the week seeing up close all that goes into coaching at the NFL level. It's something Staley has expressed interest in previously as he's enjoyed his time working with young offensive linemen on a more individual basis.

But Staley, who went to six Pro Bowls and was an NFL All-Decade player for the 2010s, is also well aware of the time sacrifice that comes with coaching. Which is why he will also consider less time-consuming things, such as media opportunities, to stay connected to the game.

"I know he's got a passion for it," Shanahan said. "I know he wants to be around football and he wants to decide if he wants to work this many hours before he jumps into it. So, he'll get a look at that this week and we'll see what he thinks."