NFL seasons are not won or lost during the league’s major free agency period, but it does do much to shape what teams’ rosters and depth charts will look like when a season begins. It’s also a tense time, with key players often moving elsewhere for more money and better opportunity; coaches and front-office staffs must bet wisely on who stays, who goes and who gets signed from the street.

The two Super Bowl teams, the Denver Broncos and Carolina Panthers, were both players in free agency in 2015, but their approaches were quite different.

The Broncos were the far more active team, in terms of arrivals, departures and re-signings, while the Panthers, who have had a more tenuous salary cap situation in recent years, were more conservative. But a number of moves by both teams had impacts on where they are today, on the precipice of winning a Lombardi Trophy.

Though the Broncos were more transaction-heavy than the Panthers in 2015, not all of those signed or re-signed made a major impact. But the handful that did highlight just how savvy the Broncos and general manager John Elway were with their contracts. The Broncos let nose tackle Terrance Knighton leave, replacing him with Sylvester Williams, and saw little drop-off. In fact, Denver’s defensive front is the very best in the league, ranking tops against the pass and third against the run during the regular season and putting up a league-leading 52 sacks. Instead, the Broncos invested in their linebackers and defensive ends, re-signing linebacker Brandon Marshall and bringing aboard ends Vance Walker (pictured above) and Antonio Smith. Marshall was the Broncos’ second-leading tackler this year, while Walker had two sacks and Smith, 2.5, with another in the postseason. Williams, Knighton’s replacement, had three sacks. They also added safety Darian Stewart, who was the Broncos’ third-leading tackler on the year and already has a postseason interception.

Tight end was also a free agency focus for the Broncos, with Jacob Tamme and Julius Thomas leaving (and the latter signing a five-year, $46 million contract with the Jacksonville Jaguars), Owen Daniels signed from the street and Virgil Green given a new deal. Daniels is costing the Broncos a maximum of $12.25 million over three years and Green, $8.4 million over three years. They combined for 58 receptions for four touchdowns during the regular season and Daniels added two postseason scores on his four receptions; the Broncos clearly chose right when it came to which tight ends to pay and how much.

But no signing meant more to the Broncos than the contract given receiver Demaryius Thomas. Thomas was initially given the franchise tag in March, worth $12.823 million for 2015. However, with no long-term job security, Thomas held out for a contract offer, which he eventually received. The five-year deal, worth a maximum of $70 million, assured Thomas would be there from Week 1 on. Thomas eventually went on to catch 105 passes for 1,304 yards and six scores in the regular season and another six passes for 52 yards in the postseason.

Most of Carolina’s free agency moves were on the defensive side of the ball. They brought aboard safety Kurt Coleman and cornerbacks Charles Tillman and Teddy Williams as well as defensive lineman Dwon Edwards. Later, when cornerback Bene Benwikere suffered a season-ending fractured leg in Week 14, the Panthers then brought aboard free agent Cortland Finnegan and two weeks later, Robert McClain. Both were smart signings—Finnegan had to replace Benwikere, but Tillman suffered a torn ACL on January 4, forcing McClain into the starting lineup. Finnegan has a postseason interception, while McClain has a 14 combined postseason tackles and three passes defensed, making the two keys to the Panthers remaining a stout, ball-hawking unit in the secondary despite injuries.

On the offensive side of the ball, the signing of Ted Ginn Jr. has proven surprisingly invaluable. Thrust into the role of No. 1 wideout following season-ending injuries to Kelvin Benjamin and Stephen Hill, Ginn totaled 44 catches on 96 targets for 739 yards, a team-leading 10 touchdowns and 250 yards after the catch. Though Ginn’s longstanding hands issues remained, he still accounted for nearly 30 percent of the 35 touchdowns Panthers quarterback Cam Newton threw in the regular season—production that otherwise could not have been possible without him.

Meanwhile, the choice to let running back DeAngelo Williams leave in free agency did not hurt the team, with the Panthers tying for the most regular-season rushing touchdowns scored (19) and the second-most rushing yards (2,282), thanks to the legs of Jonathan Stewart, Newton and fullback Mike Tolbert. And even bringing in Michael Oher, who had been much maligned in prior stops in Baltimore and Tennessee, proved to be an asset, with Oher starting every game at left tackle this year and giving up only four sacks, according to Pro Football Focus.

While the Broncos and Panthers took quite different approaches to free agency in 2015, there were a number of signings from within and without for both teams that had major impacts on their successful seasons. Now, with the Super Bowl just over a week away, many of these free agents will be important parts of their respective team’s game plans. Given the contributions made by many—particularly on defense for both teams, at tight end for Denver and the Ginn addition in Carolina—it’s possible these two teams would not be vying for the championship.

Free agency doesn’t lead to Super Bowls, no, but how teams handle it, before the season and in season, can determine just how successful a team can be.

(All stats via ESPN and all salary and contract data via Spotrac unless otherwise noted).

About Andrea Hangst

Andrea Hangst is The Comeback's NFL salary cap and contract guru. She also covers the NFL for Bleacher Report, Sports on Earth and's Orange and Brown Report. She is the host of the weekly F*BALL NFL Podcast, which can be found via iTunes or Stitcher and she is a member of the Pro Football Writers of America.