SAN DIEGO – The window for NFL teams to apply the franchise tag on players set to hit free agency begins on Wednesday and closes at 3 p.m. ET March 1.

For the Los Angeles Chargers, it provides an opportunity for general manager Tom Telesco to figure out what to do about pending free agent Melvin Ingram.

Ingram, a former South Carolina star, will be one of the top free agents in March if allowed to hit the market. With 18.5 sacks in the last two seasons, Ingram is tied for 12th in the NFL in that time period.

Paired with second-year pro Joey Bosa, the Chargers have one of the best pass-rusher tandems in the NFL.

Ingram turns 28 years old in April, and the Chargers have to figure out if he’s a good fit in new defensive coordinator Gus Bradley’s scheme, along with determining if he’s worth the long-term financial investment.

The Chargers face a difficult decision on whether they can afford to keep pass-rusher Melvin Ingram. Tom Walko/Icon Sportswire

Olivier Vernon set the bar for pass-rushers by signing a five-year, $85 million contract that included $52.5 million in guaranteed money with the New York Giants in free agency last year.

The Chargers likely would be unwilling to match that kind of deal.

The franchise tag is a labor designation that restricts a player’s potential movement in exchange for a high one-year salary. It is governed by owners and players through the collective bargaining agreement.

There are two types of designations, exclusive rights and non-exclusive. The exclusive-rights franchise tag designation means a player is bound to the team for the upcoming season. A player’s agent is prohibited from seeking offer sheets elsewhere.

The amount earned is the average of the five largest salaries at the player’s position through the end of the current year’s restricted free-agent signing period (April 21 this year), or 120 percent of the player's salary the previous year -- whichever is greater.

With the nonexclusive franchise tag, players can sign an offer sheet with another team. The original team has the opportunity to match that offer and retain the player under those exact terms, or it can allow the player to leave in exchange for two first-round draft picks from the new team.

The Chargers have used the franchise tag just six times in team history. The last time was in 2011 on receiver Vincent Jackson. The Chargers have used the transition tag just three times in franchise history.

The amount it would cost to retain Ingram for a season will depend on if he’s designated a linebacker or a defensive end. ESPN’s John Clayton projects a franchise-tag designation of $15,287,383 for linebackers and $16,988,266 for defensive ends, with a projected salary cap of $168 million.

The problem for the Chargers would be the cap hit the team would take if Ingram signed the franchise tender. The Chargers have roughly $20 million in cap space, and all of Ingram’s salary would be designated toward this year’s cap.

So it would be beneficial for the Chargers to get a long-term deal done with Ingram to lower his cap number.

According to the NFL Players Association database, Ingram is represented at Roc Nation Sports by Kim Miale, Ari Nissim and John Thornton.

ESPN’s Kevin Seifert provides all the pertinent information on the franchise tag here.