King Dunlap's contract with Chargers a model for Steelers' Kelvin Beachum

Rough is the road for a seventh-round draft pick.

The Eagles selected Auburn's King Dunlap with the 230th overall pick in the 2008 NFL Draft. It never really panned out for him in Philadelphia, even though battling through four rookie contract seasons and a restricted free agency tender is rare for a player selected that late in the draft.

He ended up in San Diego on a light two-year deal in 2013.

It's safe to say Dunlap hit his stride.

The Chargers signed him to a four-year, $28 million contract last week, and in doing it, created what's likely to be viewed as a key comparable contract in the future negotiations between the Steelers and their own former seventh round pick, Kelvin Beachum.

In fact, that deal may only be the basement of Beachum's offer.

Dunlap will turn 30 right after the start of the season, while Beachum will enter training camp at age 26. Beachum is in the final year of his rookie contract, and is scheduled to reach free agency in 2016. There are literally dozens of tackles scheduled to make more than Beachum is this year (including fellow draft classmate and teammate Mike Adams), but not many of them have been better over the past season.

Beachum was, according to Pro Football Focus, the Steelers' best offensive lineman this year, and a key component of a line that, according to Football Outsiders, was the league's sixth-best overall unit, one that allowed the fewest runs stopped at or behind the line of scrimmage.

During the offseason before the 2012 year, the Steelers were reportedly in negotiations with wide receiver Mike Wallace. The team allegedly offered Wallace a contract in the range of $50 million total over five years, a figure Wallace declined. The team modified that offer and gave it to the grossly underpaid Antonio Brown.

In Brown's situation, it was far more money than he was scheduled to earn over the coming two seasons. He was two years into his own rookie contract, one signed after being a sixth round pick in 2010.

While Brown could make the argument he's still underpaid, it was a long-term deal with guaranteed money. The Steelers would be wise to look at a similar kind of arrangement for Beachum now.

Another outstanding season in 2015 will put him in shooting distance of the top level contracts for the third-most expensive position in the league. With center Maurkice Pouncey already having received a big extension (Marcus Gilbert as well, to a lesser extent) and 2012 first round pick, right guard David DeCastro, likely playing 2016 on a team option for a large sum, the Steelers will only have so much money to spend on its steadily improving offensive line.

Making a long-term offer now to get Beachum paid would be smart, but perhaps the smarter move for Beachum will be to play out his rookie deal and force the Steelers to pay at or around market value for a high-performance 27-year-old left tackle, or place a franchise or transition tag on him for 2016.