Peyton Manning is the king when it comes to earning money from NFL player contracts. The future first-ballot Hall of Fame quarterback made close to $250 million on the field during his 18 NFL seasons spent with the Colts and Broncos.

No active player has reached the $200 million mark, by to my calculations, which do not include collectively bargained amounts for playoff money or participating in offseason workouts, which is nominal. Tom Brady leads the way with $191,904,206. Eli Manning and Drew Brees are right behind Brady at $185.99 million and $185.933 million. All three should go over $200 million in 2018.

Timing is everything with player contracts in professional team sports. Lions quarterback Matthew Stafford has impeccable timing. It puts him in a good position to retire as the NFL career earnings leader provided his current career trajectory doesn't take a drastic downturn over the next few years.

Turning pro at the perfect time

Stafford is one of the last beneficiaries of early draft picks receiving mega-deals before the 2011 collective bargaining agreement (CBA) created a rookie wage scale. As the first pick in the 2009 NFL Draft, Stafford received a six-year, $72 million deal (worth a maximum of $78 million through base salary escalators and incentives) containing $41.7 million in guarantees. When Stafford signed with the Lions, his contract was comparable to those of Aaron Rodgers and Brady despite never playing a down in the NFL.

Stafford getting his contract before the rookie wage scale drastically reduced salaries for top picks gives him a big financial advantage that is difficult for the early first-round picks operating under the existing CBA to overcome. Andrew Luck, the No. 1 pick in 2012 who is currently the NFL's highest-paid player, signed a fully guaranteed four-year rookie contract worth $22,107,998. By contrast, Stafford made $50.5 million over the first four years of his rookie deal. It's the second most an NFL player has ever made over his first four years of his first contract behind 2010 first overall pick Sam Bradford's $51.045 million. Bradford hasn't been able to sustain his slight earnings lead over Stafford because of difficulties living up to his lofty draft status.

Luck's five-year, $122.97 million extension with the Colts last offseason reset the NFL pay scale. Although Luck's deal averages $24.594 million and contained a $32 million signing bonus, this isn't enough to offset Stafford's financial head start. Stafford also received an extension after his fourth NFL season. Through five seasons, which is Luck's entire NFL career to date, Stafford maintains an almost $16 million earnings lead at $82 million to $66,107,998.

The discrepancy grows when looking at age instead of seasons played. Stafford entered in the NFL at 21 years old, which allows him to get to his higher earning years earlier than most other players. This is another advantage Stafford has that shouldn't be underestimated. Luck was a 23-year-old rookie, and he will turn 28 two days after the Colts' 2017 regular-season opener against the Rams on Sept. 10. Stafford outpaces Luck by $32,392,002 through age 27.

Willingness to exploit contract leverage

Stafford took advantage of the high salary cap numbers his rookie contract produced to get an extension in 2013 with two years remaining that exceeded his production. When Stafford signed the deal, his $20.82 million 2013 cap number was the second highest in the NFL. His three-year, $53 million extension made him the NFL's seventh highest-paid player by average yearly salary at $17,666,667.

Stafford was coming off a 2012 season that didn't measure up to his 2011 campaign in which he threw for 5,038 yards and 41 touchdown passes. Although Stafford set an NFL record with 727 pass attempts and was second in the league with 4,967 passing yards, he only threw 20 touchdown passes in 2012. His passer rating also dropped from 97.2 (fifth in the NFL) to 79.8 (22nd in the NFL) and his completion percentage declined to 59.8 percent from 63.4 percent, which was a career high at the time. Additionally, the Lions posted a 4-12 record with 21 of 22 starters returning from a 2011 playoff team.

The smartest thing Stafford did was take a short-term deal so he could reap the benefit of changing market conditions if his level of play improved, which it has. He has played his best sustained stretch of football since Jim Bob Cooter was promoted from quarterbacks coach to replace Joe Lombardi as offensive coordinator in the middle of the 2015 season. Stafford proved in 2016 he could thrive without six-time Pro Bowl wide receiver Calvin Johnson, one of the game's most dangerous offensive weapons who retired young after the 2015 season. The Lions earned a wild-card berth in 2016 with Stafford engineering eight game-winning drives and leading eight fourth-quarter comebacks, both NFL bests.

How massive will Matthew Stafford's next deal be? USATSI

Preliminary discussions for a new contract have already started. Stafford doesn't have an incentive to sign a new deal before Raiders quarterback Derek Carr, whose rookie contract is set to expire after the upcoming season. Getting Carr under contract long term is a major offseason priority for Raiders general manager Reggie McKenzie. Carr could become the NFL's first $25M-per-year player should he sign an extension.

Stafford is dealing from more of a position of strength entering a contract year now than he was four years ago in 2013. Carr raising the bar for quarterback salaries would become the new floor for any Stafford extension. The Lions allowing Stafford to play out his contract could be risky. It will be $26.4 million (120 percent of his $22 million 2017 salary cap number) to use a non-exclusive franchise tag on Stafford in 2018. A second franchise tag in 2019, another 20 percent raise, would cost the Lions $31.68 million.

The top of the quarterback market could have another dramatic shift if Stafford plays the franchise tag game, because Rodgers is expected to sign a new deal in 2018 when there are two years left on his current contract, and the Falcons will likely extend reigning MVP Matt Ryan's contract next year as well since he will be in a contract year.

Stafford, who is scheduled to make $16.5 million this season, has made more money from player contracts through age 28 than anyone in NFL history, with $110.5 million in eight seasons. He turned 29 in February.

There's a good chance Stafford will have earned $200 million by the time he turns 33 in 2021. Stafford would be slightly over $185 million by playing under two franchise tags in 2018 and '19. Depending on the timing and length of Stafford's next contract, he could be in a position for one last big payday when he's 33 or 34 years old. Eli Manning, Philip Rivers and Ben Roethlisberger were in this age range when they signed lucrative extensions in 2015.

Stafford's biggest immediate competition

Ryan, the third overall pick in the 2008 draft, is Stafford's biggest immediate threat to eventually becoming the NFL's top money earner. Ryan's $120.5 million through eight seasons is $10 million more than Stafford despite being drafted two picks later one year earlier. It's a different story when examining earnings through age 28. Stafford is $23 million ahead because he was essentially two years younger than Ryan, who turns 32 in May, as a rookie. Ryan's next contract will likely be his last big one, while that might not the case for Stafford.

Interestingly, both are represented by Tom Condon, which takes competency of representation out of the equation in determining who will get a better deal. Besides Ryan and Stafford, Condon has represented several prominent quarterbacks in recent years. Some of his quarterback clients have included Bradford, Drew Brees, the Manning brothers and Alex Smith.

Left to his own devices, Condon typically negotiates strong quarterback deals that can be construed as having a player-friendly structure. He drove a hard bargain for Brees last offseason when the 37-year-old had an astronomical $30 million 2016 cap number in his contract year. He negotiated a one-year, $24.25 million extension for Brees, giving the Saints substantial cap relief in 2016.

Factoring in the unknown variables

Stafford making over $300 million from his NFL playing contracts is conceivable, since he might not have quite hit the halfway point of his playing career. Stafford reaching the $300 million mark will require durability, a sustained earning power for an extended period of time and a continued willingness to exploit contract leverage for maximum financial gain. Stafford hasn't missed a game since 2010, his second season, when he only played three contests because of surgery to his throwing shoulder.

Competent quarterbacks are the scarcest commodity in the NFL. As long as Stafford's skills don't rapidly diminish during the extension he is expected to sign this offseason, he shouldn't have to take a pay cut on his fourth contract (unless he wants to) with the way the salary cap has been growing in recent years and quarterback salaries have been escalating. Brees and Carson Palmer are already commanding short-term extensions in excess of $20 million per year in their late 30s.

Most players aren't willing to consistently to take a hometown discount, like Brady has, so his team can improve the talent around him or retain key players in order to be more competitive. If Brady had acted like the typical player, he might have already overtaken the elder Manning at the top of the NFL earnings list but would probably have fewer Super Bowl rings.

Stafford would need to adopt an approach similar to Manning's in the latter stages of his career for Condon to leave money on the table. Manning declined to become the NFL's first $20M-per-year player when Condon was negotiating his final Colts contract in 2011. He opted for a more front-loaded five-year deal that matched Brady's $18 million average, which was tops in the NFL at that time.

Before Manning signed with the Broncos in 2012 after the Colts released him, 12 teams reportedly inquired about him once he became available. Manning narrowed his choices to four teams and picked his destination before having Condon commence negotiations instead of letting him leverage the considerable interest, which reportedly included a $25M-per-year offer from the Tennessee Titans, into a blockbuster contract. Nevertheless, he still briefly set the NFL salary bar with his five-year, $96 million deal, which lasted until Condon made Brees the NFL's first $20M-per-year player four months later.

There's also the possibility that Stafford could walk away from the game early, even though he could still be an effective starter, because he has achieved a level of lifetime security that wasn't previously possible.