Since its inception in 2006, the Designated Player rule in MLS has been affectionately known as the "David Beckham Rule," for its most famous signing. The rule allows for a team to sign up to three players to contracts that exceed the maximum salary restrictions implemented by the league.

But now MLS might be ready to add a fourth designated player, with the goal being for teams to sign more players like a Mix Diskerud or Sacha Kljestan over one Beckham-like, big-name signing.

Metro New York has learned that the league is considering adding another designated player slot to the three already allowed on each team's roster but this one will, at its core, be more of a mid-tier level signing. The mechanism, a league source said, would likely be for the caliber of a player who would be signed over the league's maximum salary restriction of $436,250 but would come under a certain number.

The league source speculated that the max-salary number for this mechanism could be somewhere between $750,000 to $1 million. Nothing is definite yet, the source said, but it is something being strongly considered by the league and is tentatively being referred to as a "Core Designated Player."

The goal would be to keep and add more players who could add something to the league, players like a Jozy Altidore, Clint Dempsey, Giovinco, or Robbie Keane. This would also help keep MLS from losing players, specifically national team players, to larger contracts overseas. Those players might not be enough of a draw to specifically justify a designated player threshold but this proposed 'Core DP' would fit certain individuals.

The rule would certainly be beneficial for the quality of the league and improving the product on the field. With a new television deal that includes a consistent television time slot Sunday evenings on ESPN2 as well as on FoxSports1, the league is flush with new money and momentum from expansion teams in Orlando and New York City.

In terms of mechanisms, the proposed rule would work not unlike the current Designated Player set-up except that this player's base salary would have certain restrictions and would fall between the maximum player salary mandated by the league and a yet to be determined amount, likely somewhere between $750,000 to $1 million.