Could a 2017 first-round draft pick do what Joey Bosa did last year and hold out of training camp while his contract remains unsigned?

Absolutely. More than one could, in fact.

With a little more than a week to go before the start of most NFL training camps, a surprising six first-round picks remain unsigned, including three of the top six. Those three are Solomon Thomas of the San Francisco 49ers (No. 3), Corey Davis of the Tennessee Titans (No. 5) and Jamal Adams of the New York Jets (No. 6). Six is an unusually high number of unsigned first-rounders for this time of the year. As of July 14, 2016, three remained unsigned. This time in 2015, only one (Marcus Mariota) was unsigned. And at this point in 2014, two first-rounders remained unsigned.

And because Thomas and Davis are represented by the same agency that represented Bosa a year ago in his contentious negotiations with the San Diego Chargers, it's not hard to connect the will-he-hold-out dots in their cases.

Bosa's holdout was over contract language and structure. The Chargers wanted to include offset language, which essentially means the team could recoup some money if it cut him and he signed elsewhere before the end of his deal. Bosa also fought with the Chargers over the schedule and structure of his bonus payments, and his holdout lasted until the end of August.

Titans receiver Corey Davis is one of six first-round picks who are still unsigned as training camp nears. AP Photo/Mark Humphrey

But these deals don't happen in a vacuum, and this year one of the complicating factors appears to be the deal signed by No. 1 overall pick Myles Garrett with the Cleveland Browns. In the words of one agent, Garrett "agreed to everything," meaning he signed a contract that includes a structure and a number of clauses that many of the players picked behind him don't want in their deals. And once the No. 1 pick agrees to something, it gets tougher for the Nos. 2 and 3 picks to argue that their deals shouldn't have it.

According to multiple agents who spoke on condition of anonymity, the first-round signing holdup has to do with contract language. These cases aren't strictly about dollar figures, as the rookie wage scale that came with the 2011 collective bargaining agreement establishes strict salary guidelines for each draft slot. But teams and agents still find things over which to fight. An example is offset language, which players fight against because they want to be able to double-dip in the unlikely event that the team were to cut them. This is why it's no surprise to see Davis still unsigned. The Titans have a reputation for insisting on offset language and often take a while to sign their first-round picks as a result. Garrett's deal includes offset language. No. 4 pick Leonard Fournette's deal, which was done two days before Garrett's, does not.

But there are other language and structure issues that cause problems. Without identifying specific teams and their 2017 negotiating positions, the agents surveyed for this story cited two examples of trouble spots:

Payment structure

A lot of agents for first-round picks like to build the deals' annual salaries around roster bonuses, keeping the base salary at or near the minimum and putting the rest of the money into a guaranteed roster bonus that gets paid out during training camp or at the start of the season.

For example, Chargers first-round pick Mike Williams (No. 7 overall) will make $1,362,730 in 2018. But of that salary figure, $807,730 is paid out as a roster bonus that's fully guaranteed at signing but doesn't actually land in his bank account until the fifth day of training camp. This is preferable in part because team-imposed fines are figured as a percentage of the base or "Paragraph 5" salary, which in Williams' case in 2018 will be $555,000. Ironically, this was the major hangup with Bosa.

Garrett's rookie deal with the Browns does not include a roster bonus structure. His 2018 pay will be $1,847,375, all Paragraph 5.

Joey Bosa's holdout didn't hurt his on-field production, though he missed the first four games of the season with a hamstring injury. Jake Roth/USA TODAY Sports

Language that imperils guarantees

We reported not long ago about the NFLPA looking into some of the language teams were trying to put into rookie deals this year. A lot of that language is in Garrett's deal. Garrett's contract allows the team to void his guaranteed salary (and convert it to per-game roster bonuses) for a wide variety of reasons, including team-imposed fines.

Example: Garrett's contract, a copy of which ESPN obtained while reporting on this story, spells out a variety of ways the player can find himself in default and find that his guaranteed money is no longer guaranteed. These range from failed physicals to league-imposed drug suspensions to team-imposed fines. One part of that very long section says that Garrett is in default if he "takes any action that materially undermines the public's respect for, or is materially critical of, Club, Player's teammates or Club's ownership, coaches, management, operations or policies." Taken literally, this could mean that Garrett loses his guaranteed money if he questions a defensive coordinator's playcall.

It seems obvious why players and agents would want to strike from deals as much language as possible that would allow the teams to void guarantees. And if you're wondering why your team's first-round pick hasn't signed yet, odds are his agent is wrestling with the team over something like this.

Also unsigned are No. 10 pick Patrick Mahomes II (Kansas City Chiefs), No. 24 pick Gareon Conley (Oakland Raiders) and No. 25 pick Jabrill Peppers (Cleveland Browns). The Chiefs just changed general managers, which could help explain Mahomes. And Conley and Peppers were picked in a tricky area of the first round at which contracts stop being fully guaranteed. No. 21 overall pick Jarrad Davis (Detroit Lions) was the last first-rounder this year to have his four-year contract fully guaranteed. No. 22 pick Charles Harris of the Miami Dolphins got 97.31 percent of his deal guaranteed, and No. 23 pick Evan Engram of the New York Giants got 96.49 percent fully guaranteed. Conley also is dealing with an off-field issue that could be holding up his signing.

Just because the rookie deals are slotted doesn't mean these negotiations can't get messy. As Kevin Seifert wrote last month, holdouts have become increasingly rare in the NFL. But there are some circumstances at play here that could lead to one or more this summer.

The good thing for fans who might be worrying about their unsigned first-round pick? It's not as if these guys can sign anywhere else. And while everybody wants their rookies to show up and start learning as soon as possible, it's worth noting that Bosa held out until the end of August, missed the first four games of the season while getting his body in shape ... and still managed to record 10.5 sacks and win the Defensive Rookie of the Year award.