The old "poison pill" trick, offering a contract with an oddity that one franchise could accommodate more easily than another -- in this case, a salary that gets very high in its final year -- had long been allowed under the NBA rules that govern restricted free agency, but it had never been as effective as in the case of Jeremy Lin.

No matter how loaded the offer sheet that a team presented to a free agent, the player's original team has long had the right to match (though before 2005, there were more limitations in this regard) and almost always did. The thinking was that even if you didn't want the player for that much money, you had two choices: You could suck it up and pay the player the big salary and associated fees, or you could eventually find another team that would and get something back in a trade. Rudy Gay, Paul Millsap, Josh Smith -- in recent years teams made noises about recruiting all of them that way, but none moved.

With the NBA's new collective bargaining agreement, however, Houston realized it was time to revisit that logic. The more punitive luxury tax might make a "poison pill" something another team would choke on. The medicine was old, but the effect new -- and it took the Knicks, and even the people who designed the new CBA, by surprise.

"The rate goes up for every $5 million, so the tax due to Lin would have depended on how much salary the Knicks would have had without Lin," ESPN cap expert Larry Coon said. "For example, if they are right at the tax line without Lin, then his $15 million will cost them $28.75 million in tax. If they're $10 million over the tax line before Lin, then his salary will cost them an extra $47.5 million in tax."

That's a lot of money, even for one of the richest teams in sports.

Jeremy Lin was the apple of the Big Apple's eye -- a major draw who delighted fans and inspired global interest in the Knicks with major bottom-line implications. He was, until last weekend, seen as a lock to return to New York at any cost.

Then the Rockets agreed to give Lin a huge pay bump in the third year of his three-year offer, which, if the Knicks matched, would trigger a huge tax bill for New York.

This deal was diabolical for the Knicks in another regard, too: Lin would have been almost untradable if the Knicks had signed him.

The rules have long said that such players (restricted free agents whose original teams match another team's offer sheet) can't be traded in the first year of the deal without their consent. In the second year, Lin's contract would have been essentially a two-year, $20 million deal -- a much less attractive contract than three years and $25 million. What's more, the trade partners would have been teams willing to offer a player worth about $5 million, to match the Year 2 salary, but also be able to pay $15 million (plus, in some cases, luxury taxes) the next year. Not a lot of teams fit the bill.