By Michael Hurley, CBS Boston

BOSTON (CBS) — Heading into the “legal tampering” period of NFL free agency, some analysts suggested that Trey Flowers was the best player available in free agency. Not the best defensive end, not the best pass rusher. The best player. Period.

While that point, like anything in sports, can be debated, the fact that the Lions were willing to shell out a reported $16-$17 million annual salary over five years to obtain the services of the 25-year-old does lend quite a bit of credence to the suggestion.

And that shouldn’t be forgotten here in New England, in the wake of Flowers heading out of town to reunite with Lions GM Bob Quinn and head coach Matt Patricia. The Patriots drafted and developed Flowers and then happily sat by idly, passing on the opportunity to place the franchise tag on him, and wishing him a fond farewell as he headed off to break the bank elsewhere.

Typical Patriots.

Typical Belichick.

Really, while no two stories are ever the exact same, you have to consider how and where the Patriots acquired Flowers in the first place. The Patriots drafted Flowers at the top of the fourth round of the 2015 draft. It was such a noteworthy event that … it didn’t even warrant its own story on this here website. Flowers had to share those honors with Tre’ Jackson and Shaq Mason, both of whom were also selected in that same fourth round.

As a rookie, Flowers played in all of one game. He was inactive throughout the season and was eventually placed on IR on Dec. 1. Rookie season over. No tackles, no forced fumbles, no sacks, no picks. No nothing.

Not much was made of Flowers’ presence on the roster in the offseason that followed, and he was generally quiet through the first half of the 2016 season. Then, the Patriots and Flowers unleashed that untapped potential, and he broke out for seven sacks and 23 total tackles in the next seven games. In Super Bowl LI against the Falcons, he picked up 2.5 sacks on Matt Ryan, one of which helped push the Falcons out of field-goal range late in the fourth quarter.

A star was born.

Flowers put forth a solid season in 2017, establishing himself as a force on the edge and the interior, as a pass rusher and a run stopper. He did the same thing in 2018, making a critical sack of Patrick Mahomes in the AFC title game to push the Chiefs out of field-goal range before halftime and contributing to the New England defense holding the No. 2-ranked Rams offense to just three points in Super Bowl LIII.

With that, Flowers quite quickly went from unheralded fourth-round pick, to mostly forgotten rookie, to suddenly being the best player available in free agency.

And to be clear, the 25-year-old should remain a consistent, impactful player for the Lions. But as is the case with most every big-money contract in the NFL, it’s nearly impossible for any player to produce at a level that matches the dollar cost that is attached to these free-agent mega deals.

With his official departure now set to take place on Wednesday, Flowers joins a long list of players whose value has been absolutely maximized by Bill Belichick and the Patriots coaching staff before that player is set free to make truck loads of money elsewhere.

To wit:

David Givens was drafted in the seventh round (253rd overall) in 2002. He did almost nothing as a rookie (nine receptions, 92 yards, 1 TD), but then contributed in big ways to back-to-back Super Bowl wins. Givens caught five touchdowns in the 2003 and 2004 postseasons, after catching six touchdowns in the ’03 regular season. In 2005, he ranked second on the team in receiving. It was time for him to make his money.

Belichick let Givens make that money elsewhere. The Tennessee Titans, with a five-year, $24 million contract, were happy to oblige. Givens would play just five games with the Titans before tearing his knee; he’d never play in the NFL again.

A close comparison to Flowers could be found in cornerback Asante Samuel, who was drafted in the fourth round by the Patriots in 2003. Early in his career, he contributed to a pair of Super Bowl wins. In his walk year, Samuel led the league with 10 picks. The Patriots, unprepared for life without the corner, placed the franchise tag on him for 2007, before letting him walk via free agency in 2008; the Falcons gave him a six-year, $57 million deal with $20 million guaranteed.

Maybe the greatest examples of Belichick absolutely maximizing the value of players could be found in Malcolm Butler and Mark Anderson. Butler’s story is well-known, as he was an undrafted free agent out of West Alabama (Dont’a Hightower once said he had never even heard of West Alabama when he himself was playing at the real Alabama) who won the Super Bowl with a game-saving interception. Butler ended up working as the team’s top cornerback for several years, all while making peanuts relative to his peers. When it came time to finally pay him, Belichick was happy to let the Titans do just that, as Tennessee offered Butler a five-year, $61.25 million deal with $30 million guaranteed. (Pro Football Focus rated Butler as the 57th-best cornerback in the NFL in 2018.)

Anderson joined the Patriots as a disappointing five-year veteran in 2011. He racked up 10 sacks for the Patriots that season, after he had recorded 13.5 combined sacks over the past four seasons. Belichick happily said bon voyage to Anderson after the season; the Bills readied a $19.5 million contract with nearly $8 million of guaranteed money. Anderson would play just five games for the Bills in 2012, his final year in the NFL.

The other examples aren’t hard to find: Dion Lewis was acquired for nothing and didn’t make much money during his three seasons in New England, where he racked up 1,483 yards from scrimmage with 19 touchdowns in 36 games (playoffs included). The Patriots let him walk as a free agent, where he was given a three-year, $20 million contract by the Titans. BenJarvus Green-Ellis went from undrafted free agent to 1,000-yard rusher with the Patriots, carrying the ball more than 500 times from 2008-11. He massively outperformed his contract, and when it was time for a new one, Belichick let the Bengals give it to him — in the form of a three-year, $9 million deal.

The list goes on, and it leads to the Patriots getting 55 games, 26.5 sacks and two Super Bowl wins from Trey Flowers, all while paying him a total of $4.15 million. Flowers will make more than $4 million from the Lions before Week 5 of the 2019 season.

Why are the Patriots the Patriots? This helps. They paid Trey Flowers just over $4 million over four years. He'll make more than $4 million by … Week 5 next year. pic.twitter.com/HSRsTb4Cth — Michael Hurley (@michaelFhurley) March 11, 2019

It is, really, a tale as old as time itself — Bill Belichick squeezing every last ounce of value out of a player, watching that player make a whole lot of money from another team, and then going about his business as the architect of the most successful football franchise over the past two decades and perhaps ever. Belichick is, as always, on to the next one.

That’s not to say that the story always ends poorly for the players involved, or that the Patriots always emerge without issue. Samuel went on to make a couple of Pro Bowls during a time when the Patriots really could have used a top cornerback. Lewis had his second-highest total of yards from scrimmage last season.

The Patriots also don’t limit themselves from spending. They’ve paid top-of-the-market money to keep guys like Vince Wilfork, Devin McCourty, Rob Gronkowski, Stephen Gostkowski, Randy Moss, Logan Mankins and Jerod Mayo. Those decisions have worked out well. They’ve also spent heavily in free agency a few times: Darrelle Revis, Adalius Thomas, Rosevelt Colvin, and Stephon Gilmore come to mind. Results there have been more mixed, but generally positive.

But more often than not, Belichick has proven — among other things — to be quite adept at when to assess that a player’s dollar value simply cannot be equaled in terms of production on the field. That is to say, while Flowers is worth the money in the sense that he has earned it, Belichick’s assessment is that there would be no way to squeeze $17 million worth of production out of Flowers every year for the next five years. It was a touch easier to maximize that $4 million cost spread out over the past four years.

In the meanwhile, the Patriots will pay Michael Bennett a tick over $7 million in 2019, before receiving a third-round compensatory pick for Flowers in 2020. It’s that commitment to careful spending that’s allowed the Patriots to sustain a decades-long run in a league where most runs of success capsize after three or four years at best. Other than the Patriots, no team is constantly, perpetually playing for a Super Bowl year after year … after year.

Trey Flowers is gone, now a very, very wealthy man. And the Patriots Machine rolls on.

You can email Michael Hurley or find him on Twitter @michaelFhurley.