"Plenty of players have been flashes in the pan for six games," one NFL executive told ESPN's Mike Sando. "Only San Francisco knows how much of it is real and how much is not."

Quarterback Jimmy Garoppolo's five-game audition for the San Francisco 49ers is about to come to a close, and you can bet the coaches have liked what they have seen out of the four-year veteran. While Garoppolo has started just six games over the course of his NFL career, he has won each of them while looking as poised and in command of the offense as a top-tier veteran.

Garoppolo's 1,250 passing yards while starting for the 49ers are the most by a quarterback during his first four starts in franchise history. In fact, that total is the most by a quarterback in his first four starts with any new franchise.

The 49ers have two options to retain Garoppolo beyond Sunday's game against the Los Angeles Rams. The first would be to use the franchise tag, which would pay the quarterback approximately $23.5 million on a one-year deal. Salary cap space isn't an issue for San Francisco, which is expected to have among the largest surplus of available money in the league.

The second option is to sign Garoppolo to a long-term deal, which is where things may get a little more complicated but still very doable. While the 49ers quarterback has looked elite during his time with the team, it is his limited number of NFL starts that might make some wary of committing a lot of long-term money to him. Of course, it isn't often a potential franchise quarterback becomes available for the cost of only a second-round pick, especially one as highly regarded and sought after as Garoppolo.

In June, Oakland Raiders quarterback Derek Carr signed a new five-year, $125 million deal, which at the time was the largest contract in the history of the NFL. Two months later, it was eclipsed by a new five-year, $135 million deal for Detroit Lions quarterback Mathew Stafford.

One NFL executive told Sando he would have a difficult time paying Garoppolo more than Carr but would be okay with paying him a similar amount.

"Logically, it would not make sense to go higher than Carr, but if you pay him a mil a year more, who cares?" the unnamed executive said. "It is just a little hard psychologically."

The interesting part of a long-term deal is how the franchise tag might come into play when determining the cost, even if San Francisco were to refrain from using it.

Using the franchise tag in 2018 would cost the 49ers an estimated $23.5 million. If they were to use it again in 2019, that cost would balloon by 20-percent to $28.2 million. Over two seasons, using the franchise tag would cost the 49ers $51.7 million, which comes out to $25.85 million per year. San Francisco could use that number as a rough guideline for an annual salary on a long-term contract.

If the 49ers used that train of thought, it would equate to a five-year deal worth just over $129 million. That would be more than Carr's contract, less than Stafford's, and still thrust Garoppolo, who will earn about $434,000 this season, into the upper echelon of NFL salaries.

You can read the entire ESPN article here. (ESPN Insider required)