JACKSONVILLE, Fla. -- There was one surprise in the last dash to use the franchise or transition tags before 4 p.m. ET Monday, and it’s one that’s potentially very good for the Jacksonville Jaguars.

The New England Patriots tagged kicker Stephen Gostkowski, which means free safety Devin McCourty will become a free agent unless the sides work out a new contract between now and 4 p.m. ET March 10. If that doesn’t happen and McCourty does hit the open market, he should be the Jaguars’ No. 1 priority.

There are other big-name players that will be available -- defensive tackle Ndamukong Suh, tight end Julius Thomas, receiver Randall Cobb, and right tackle Bryan Bulaga could top the list -- and the Jaguars likely will pursue some of them. However, the Jaguars can find other, admittedly somewhat lower-caliber options at those positions, either through free agency or the draft.

That’s not the case at free safety. It’s not a particularly good crop in free agency, and the draft pool isn’t considered very good, either. So if the Jaguars are going to fix the biggest issue on defense in 2015 they must go after McCourty.

For Gus Bradley’s defense to perform at its best it must have a physical strong safety who can play near the line of scrimmage and a free safety with the range and athleticism to cover the width of the entire field. Bradley likes to play single high safety a lot, and right now he doesn’t have one that can do that.

Josh Evans, a sixth-round pick in 2013, has started 24 games at the spot but has no interceptions, no forced fumbles, two fumble recoveries, and just two pass breakups. The 6-foot, 205-pounder also has had issues with tackling, though he improved significantly in that area as the 2014 season progressed and was the Jaguars' third-leading tackler (90) in his second season.

McCourty is a perfect fit. He’s big enough (5-foot-10, 195 pounds), fast enough (he’s a converted cornerback), and smart enough to complete what is turning out to be, at worst, a very solid secondary. It would be a young secondary, too. McCourty is 27, which would make him tied for the oldest among players in the secondary that are under contract for 2015.

McCourty also has the trait that has been missing from the Jaguars’ secondary for a long time: he makes plays. He has 17 interceptions, eight forced fumbles, and 58 pass breakups in his first five seasons, which averages out to 3.4 interceptions, 1.6 forced fumbles, and 11.6 pass breakups per season. The Jaguars’ entire group of defensive backs had three interceptions, four forced fumbles, and 26 pass breakups in 2014.

McCourty is unquestionably the top free safety on the market. He’s certainly not going to command Suh money, but the Jaguars might have to spend the kind of money that San Diego did on Eric Weddle (five years, $40 million) and Seattle did on Earl Thomas (four years, $40 million).

They should do it without hesitation.