The battle lines were clearly defined. Proponents of efficiency and advanced stats held up Gay as a symbol for everything that was wrong with putting points on a pedestal.
On the other side, the "eye test" crowd pointed to Gay's prototypical size and athleticism as sufficient reasons not to deal him. Talent was supposed to win out.
Gay's lackluster performance in Toronto, and Memphis' playoff success without its biggest name, provided vindication to one side, but also proved to be a landmark moment for how we evaluate players.
More and more, a very specific kind of production is beginning to take precedent over perceived on-court abilities. In this sense, Gay has played the role of a constant, allowing us to gauge the temperature of the league by looking at how his value has changed.
And while it may not tell the whole story, simply evaluating the return Toronto received for Gay can give you a good idea of how much change there has actually been.
Last season, Gay was traded for a legitimate starting point guard in Jose Calderon, an exciting young frontcourt prospect in Ed Davis and a second-round draft pick.
As for this year's haul? Yahoo! Sports' Adrian Wojnarowski and Marc Spears have the details:
The Toronto Raptors have reached an agreement in principle to send Rudy Gay to the Sacramento Kings, league sources told Yahoo Sports.
The Kings will send Greivis Vasquez, John Salmons, Patrick Patterson and Chuck Hayes to the Raptors. The Kings will also acquire Quincy Acy and Aaron Gray in the deal, sources said.
Gay was receptive to the trade, a source close to him told Yahoo Sports on Sunday night. "He's very motivated and determined to prove people wrong right now," the source said.
Gay was moved for three essentially expiring contracts (Vasquez, Patterson and Salmons) and the undesirable deal of Hayes. No draft picks, no players with another full season on their rookie deals. Just some depth and the right to match on a few young restricted free agents. That's it.
To be fair to Gay, though, there are a lot of variables that come into play.
When the Raptors initially traded for him, it was a desperation move by former Raptors general manager Bryan Colangelo to keep his job. When you're drowning, you'll pay a heck of a lot more for a life preserver than you would on land.
It was always pretty clear that Colangelo's replacement, Masai Ujiri, would rebuild at some point, which would seem to naturally lower the asking price for Gay. Who is doing the trading and the situation of a team can matter as much as who is actually getting traded.
That isn't to say that the severe decline in Gay's production didn't play a large role as well.
This season, Basketball-Reference.com indicates that Gay is on track to become the first player since 1958-59 to average more than 18.5 attempts per game while shooting less than 40 percent from the field and averaging fewer than 2.3 assists. His levels of inefficiency and ball-stopping have been historic.
Of course, there was the contract situation playing a role as well. Whereas Gay was previously viewed as a potential savior, he may be seen now as more of a low-risk rental for Sacramento.
Gay's ability to decline his player option and become an unrestricted free agent may or may not have lessened his actual trade value, which isn't exactly typical.
If Gay really does leave $19 million on the table to secure a long-term offer elsewhere this offseason, where does that leave Sacramento? The Kings will have basically found a taker for Hayes at the price of losing the ability to match any offer on Patterson or Vasquez—two players they may not have kept beyond this year anyhow.
It all brings about an interesting question. Has Gay's value declined so drastically because of his decreased production or has it declined because of an increase in awareness around the league?
If finding value is all about identifying market inefficiencies, we may be dangerously close to a reversal on Gay's perception.
Can a player be so overrated that he eventually becomes underrated? Can inefficient, high-volume scoring become so derided that it eventually becomes worth targeting?
When Toronto traded for Gay last year, it was behind the curve. But now, there's a good chance that Sacramento may be ahead of it.
It won't be long before Gay will serve as a measuring stick once again. What kind of offer he commands in free agency, either this year or next, will be another critical moment in the analytics movement. Will the biases be as pronounced as they once were in an era that relied almost solely on scouting?
Gay's next deal will allow us to gauge once again how the league both values and perceives players of his ilk. Right now, it's clear that Gay's value has sunk.
Whether it rises again will tell us an awful lot.