A few things to know:
General terms: This is a four-year, $34 million deal with an $8.5 million average.
Guaranteed money: Long gets up to $16 million guaranteed. Wait, if it's guaranteed, why are the words "up to" necessary? Because some guarantees are conditional. In this case, it's pretty safe to say $16 million is guaranteed. Long gets a $5 million signing bonus. That is fully guaranteed. His $3 million base salary for 2013 is also fully guaranteed. The Rams guaranteed $8 million in base salary for 2014 as well. The full 2014 base salary is guaranteed if Long is healthy. Half of the $8 million is guaranteed if Long is injured. The remaining $4 million is guaranteed regardless if Long is on the Rams' roster on the final day of the 2013 league year.
Incentives: Long can earn another $375,000 per year in incentives based on playing time and playoff appearances or Pro Bowl honors.
Cap charges: Long's deal counts only $4.25 million against the cap this year. The cap charges rise to $9.25 million (2014), $10.5 million (2015) and $10 million (2016).
Flexibility: The Rams could get out of this deal comfortably after the second season. The team of course hopes Long plays all four seasons at a high level. However, the relatively small signing bonus gives the Rams flexibility down the line. Long's deal would count $2.4 million against the cap in 2015 if the team released him after two seasons. That would be an insignificant amount of dead money for a starting left tackle with a Pro Bowl pedigree.
The verdict: This looks like a good deal from the Rams' perspective. They stayed disciplined in negotiating the contract. They even let Long leave their facility after three days of meetings in St. Louis. That was risky because they could have lost a player they wanted, but they still got their man, and they did it with what amounts to a two-year bet. If Long were to suffer a catastrophic injury this season, the Rams would be on the hook for $7.6 million in cap charges beyond 2013, but they're on the hook for $3.6 million of that in the form of bonus proration, anyway. That seems like a risk the Rams can afford to take because they will have so many young players under rookie contracts as the seasons progress.