John Earnhardt, Cisco's head of corporate PR, is leaving the company after 16 years, taking a job at Visa.

With the old CEO leaving and the new one coming, Earnhardt told Business Insider that this was a good time for him to leave as well.

In July, Cisco will formally have a new CEO for the first time in 20 years.

There's a delicate dance going on inside the company. Incoming CEO Chuck Robbins, who has worked at Cisco in the sales organization since 1997, will need to build his own brain-trust, extracting himself from Chambers' power players.

A lot of employees suspect Chambers will still be running the show from his job as executive chairman, we're told. Chambers has vehemently denied this, insisting that Robbins will be making the decisions, and he'll be acting as his "wing man."

But Chambers still holds incredible power in the company and is staying on as executive chairman Robbins' boss.

All eyes inside the company will also be on the company's most powerful players, the star engineers known as Mario Mazzola, Prem Jain, and Luca Cafiero, who have had Chambers' ear for decades.

This team built many of Cisco's most important products via a vehicle known as "spin-ins," which allowed Cisco to fund the product development and then pay their teams millions of dollars when the products were completed.

These engineers have tried to retire a couple of times, but Chambers epeatedly convinced them to come back. They are currently running its most important business unit, Insieme. That's the unit responsible for Cisco's flagship switch, the Nexus 9000, and the software product helping Cisco fend off new attacks from VMware and a host of startups that have created new network technology that threatens Cisco.

Inside Cisco, these engineers are hugely respected.

Sources close to Cisco tell us that Mario Mazzola and gang are still operating Insieme like an independent fiefdom inside the company, and that this team was spared from the massive 25,000-person reorg of Cisco's engineering team last fall.

It seems likely that some of Chambers' brain-trust will follow Earnhardt's lead and leave. And it will be interesting to see how the Insieme team and its powerful leaders fair under the new CEO.

NOW WATCH: Here Are The Handicaps For A Bunch Of Celebrity Golfers

See Also:

Cisco's outgoing CEO John Chambers just told this amazing story about himselfCisco's new CEO choice is a shockerHere's what Cisco employees think about their new CEO

SEE ALSO: Cisco's new CEO just said something that could make employees wary