In the NFL, like most other businesses, it’s often about who you know as much as what you can do. But that timeless truism has been taken to the extreme lately. With general managers and coaches on short leashes and franchises demanding immediate results, team officials are less willing than ever to gamble on unfamiliar commodities.

There are several teams that exude this newly prominent principle, none more so than the organization I’ve covered for the last 15 years, the Chargers.

San Diego opted for a top-down rebuild prior to the 2013 season, hiring GM Tom Telesco away from the Colts and head coach Mike McCoy from the Broncos.

Since Telesco came aboard, he has brought in several former Colts players, including Donald Brown, Kavell Conner and Ricardo Mathews. He’s also reunited some ex-Broncos players with McCoy, including two of this offseason’s additions, Orlando Franklin and Mitch Unrein.

It trickles down to the assistant coaches, too. When the Chargers needed more depth on the offensive line, they reunited former Bills swing tackle Chris Hairston with offensive line coach Joe D’Alessandris.

Signings like this occur on every team in the league. However, sometimes the deeper connections are missed by casual fans.

For example, no one blinked an eye when the Chargers added former Nevada linebacker Brock Hekking as an undrafted free agent. But how did that deal take place? Nevada’s head coach, Brian Polian, was a high school teammate of Telesco’s. And if that Polian name sounds familiar, it’s because Brian is the son of Bill Polian, who served as Telesco’s mentor in Indianapolis.

It’s no surprise, then, that San Diego’s coaching staff features two former players with close ties to the Polians — Frank Reich and Pete Metzelaars. In fact, Metzelaars played at Wabash college with Scott Boone, who was Hekking’s defensive coordinator at Nevada.

Hekking is not the only one of Boone’s former pupils on San Diego’s roster. When Boone was the defensive coordinator at William & Mary, he coached defensive tackle Sean Lissemore.

“I sent [Lissemore] a message the other day and told him to look after Brock for me,” Boone said.  “I hope [Lissemore] takes Brock under his wing because they’re similar guys…both [are] classic overachievers. They got where they got because they play really hard and work really hard.”

And because of who they know.

The Chargers are hardly the exception.

Chip Kelly has not been shy about about stocking his roster with familiar faces. There are eight former Oregon players on Philadelphia’s roster, including new linebacker Kiko Alonso, who was acquired in exchange for LeSean McCoy. Two more ex-Ducks arrived in the 2014 draft, when Philadelphia selected WR Josh Huff in the third round and DE Taylor Hart in the fifth.

Kelly’s fondness for familiarity is not limited to Oregon products. He has an affinity for all Pac 12 players, as he knows them well from his days ruling the conference.

The Eagles have more than 20 Pac 12 players on their roster, including the first two picks from this year’s draft class, USC WR Nelson Agholor and Utah CB/S Eric Rowe.

Kelly has been criticized for drafting so many Pac 12 players, not that he cares.

“Just because we have a familiarity, if someone wants to say that’s a concern, that’s OK,” Kelly said. “You know when you’re going to take them, that’s what they’re going to do. But I’m not not going to take one because I’m afraid someone’s going to say something about them.”

Over in Carolina, Ron Rivera has followed Kelly’s trend of plucking familiar faces from the West Coast and moving them eastward.

Rivera, who was the defensive coordinator in San Diego before taking the head coaching job with the Panthers in 2011, has added several former Chargers players to his roster. He has re-tooled his offensive line with Mike Remmers and Tyronne Green and added depth to his backfield with Mike Tolbert, Fozzy Whittaker and Jordan Todman.

Rivera even reached all the way back to his Chicago days earlier this offseason when the Panthers added 13-year veteran Charles Tillman.

“I think Coach Rivera was one of the main reasons why I wanted to be here,” Tillman said upon signing. “He’s a guy that I had a lot of respect for when I was in Chicago. I love his leadership and his qualities as a coach and he’s done a good job with the Panthers. There’s a good group of guys here like Thomas Davis, Greg Olsen, Luke Kuechly and Cam Newton. I got a good vibe here.”

The idea of players reuniting with their former coaches has become so commonplace it’s made free agency almost predictable.

I remember last November when the Titans released OLB Shaun Phillips. Most major media outlets expected him to return to Denver, where he had spent the 2013 season. Over here on Football Insiders, we were preaching to watch out for the Colts, having seen firsthand how close Phillips and Indianapolis defensive coordinator Greg Manusky had become during their time together in San Diego.

Days later, Phillips was wearing horseshoes.

It’s become so easy to predict where players are going to land — just follow the coaching trail — that players have even begun calling their shots. Seahawks pass rusher Bruce Irvin, upset that Seattle declined the fifth year option on his rookie contract, essentially announced his intention to join former defensive coordinator Dan Quinn in Atlanta next season.

Ex-Seahawks coaches are good for having their former pupils follow them around the league. How else do you think Chris Clemons and Red Bryant ended up in Jacksonville?

So don’t be surprised when you see the Falcons take a flier on a guy like Leonard Hankerson (reuniting him with Kyle Shanahan). Or when Todd Bowles brings Antonio Cromartie with him from Arizona. Or when the Cardinals sign Cory Redding and A.Q. Shipley, who played with Bruce Arians back in Indianapolis.

Heck, the Bengals like familiarity so much brought back three of their former players this offseason, each of whom played elsewhere last year: Michael Johnson, Pat Sims and Brandon Ghee.

This is the NFL, where now more than ever, it’s all about who you know.

Want to talk more about these handshake deals? Join Michael Lombardo for his weekly NFL Chat on Friday at 2pm EST. But you don’t have to wait until then … you can ask your question now!