FOXBOROUGH, Mass. -- With the calendar turning to March, it brings the start of free agency that much closer. Teams can negotiate with player agents for unrestricted free agents from other teams starting March 12, with the free agency officially starting on March 14.

Meanwhile, teams can negotiate extensions with their own free agents at any point up until that time, which highlights the importance of understanding the financial market at various positions.

Nate Solder could command top dollar as a free agent, especially if he's willing to walk away from New England. AP Photo/Mark Humphrey

With this in mind, let's consider what ballpark the New England Patriots and free-agent-to-be left tackle Nate Solder might be in when discussing a possible deal (and then continue with others, such as running back Dion Lewis, in the coming days).

Good timing: Solder turns 30 on April 12 and has played seven NFL seasons. He enters free agency after having signed a two-year, $20.6 million extension prior to the 2015 season, which was the final year of his rookie contract. He is viewed as the top left tackle on the market after being named a Pro Bowl alternate in 2017.

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Market watch: Last offseason, Matt Kalil (5 years, $55 million), Andrew Whitworth (3 years, $33 million) and Riley Reiff (5 years, $58.75 million) all signed deals that averaged between $11.1 million and $11.75 million per season. In 2016, Cordy Glenn (5 years, $60 million), Eric Fisher (4 years, $48 million) and David Bakhtiari (4 years, $54 million) inked deals that averaged $12 million per season and up.

Patriots cost replacement analysis: As director of player personnel Nick Caserio recently explained at the MIT Sloan Sports Analytics Conference, when it comes to a free agent, "There is a cost component that certainly comes into play relative to their role and relative to the replacement cost or replacement player behind them." What could stress the Patriots is uncertainty with a possible replacement option, as 2017 third-round pick Tony Garcia missed all of his rookie season with an undisclosed illness, and the team's top veteran backups from 2017, Cameron Fleming and LaAdrian Waddle, are also unrestricted free agents.

Final analysis: Solder seems to be in a strong position, especially with media analysts noting this isn't considered a strong year in the draft at left tackle. The top of the current market for offensive tackles is slightly more than $13 million per season, which Solder could potentially command on the open market if he's open to signing elsewhere. If remaining in New England is more of a priority for him, which means possibly not maxing out on the open market, a deal in the $11 million to $12 million-plus range per year seems realistic and fair.