What Is a "Core Player" and Why Do We Care?

Since the offseason, rumors of a fourth designated player slot being added to rosters in Major League Soccer have been circulating, popping up with some regularity. Now, with the summer transfer window about to open on July 7th, the rumors are back and looking likely to be true.

Ives Galarcep is reporting for Goal.com that the fourth designated player slot will be added before the transfer window in the form of a "core player" roster spot. How, exactly, a core player differs from a designated player remains to be seen, but Galarcep's sources seem confident that the change to the roster rules will be made soon.

In concert with the rumors surrounding the new rule come rumors of new acquisitions around the league. Most notably, Mexican international Giovanni Dos Santos has been heavily linked to the LA Galaxy, a team with three heavily entrenched designated players already and one that would need the core player rule to add another star to their lineup.

Closer to home, the possibility of the core player rule makes sense for the Portland Timbers, who have been long rumored to be shopping for a new designated player, in addition to Fanendo Adi, Liam Ridgewell, and Diego Valeri. The Timbers' semi-public pursuit of a high profile player for the team has lead to significant speculation that Adi could either have his contract paid down below the designated player threshold or could even be sold on, less than a year after the Timbers purchased him. With the core player rule in place, neither of those possibilities are necessary for the Timbers to add their own fourth high paid player.

What makes the core player rule even more interesting is the fact that it appears to be distinct from the designated player rule and will likely have some unique twists and turns governing it. Previous reports from the Orlando Sentinel have the core player spot coming with some financial backing from the league, making it look like a subsidized designated player slot and incentivizing teams to bring in talented players from outside the league.

What do you think of the rumored "core player" rule? How would you use it?