Remember the incentives added to Tom Brady and Rob Gronkowski's contracts before the start of last season -- the ones that neither of them reached? They could have the potential to impact things this spring, particularly with Gronkowski.

After consulting with former sports agent and current contributor to CBS Sports Joel Corry, here's how.

Both players have contracts that expire at the end of the 2019 season. Brady has a base salary of $14 million and a cap hit or $27 million, while Gronkowski has a $9 million base salary and just under a $12 million cap hit.

In most cases, salaries cannot increase for one calendar year with a renegotiation, but contracts can be restructured multiple times for cap purposes without the one year limitation applying. Brady's incentives were added around August 10, but technically the quarterback did not have his salary increase because he didn't earn any of his incentives. His cap number didn't increase either, since $10 million was turned into a signing bonus.

Therefore, Brady would have no issues with a potential contract extension, which seems likely to happen given his current deal is up at the end of the year, and also to spread out his $27 million cap hit.

Meanwhile, it's not as straight forward with Gronkowski.

The Patriots tight end did earn $812,500 more than he was scheduled to make in 2018 because $1 million was added to his per game roster bonuses. So even though he didn't hit any of his performance-based incentives, he still earned more money. This means nothing besides a basic contract restructure for cap space cannot happen with him until roughly Aug. 30, the time the incentives were added last summer.

This shouldn't impact the Patriots and Gronkowski too much because No. 1, he could potentially retire, and No. 2, if he does return his contract would likely only be tweaked to free up cap space, not increase what he's getting paid. Based off his 2018 production, a $9 million base and just under $12 million towards the cap, a potential contract change shouldn't be an issue because the only way his deal would be changed is because of a restructure for cap space.

Bottom line, Brady has no lingering impact from his 2018 incentives, while Gronkowski has some limitations, but they shouldn't be an issue.