The Denver Broncos quickly moved in and closed a deal with Wes Welker. (Elsa / Getty Images)

Even by Boston sports standards, this was a shock — perhaps the biggest shock since that baseball slipped under Bill Buckner’s glove.

“Say it ain’t so, Wes,” Boston Celtics Coach Doc Rivers said of the news that free agent wide receiver Wes Welker would be leaving the New England Patriots and Tom Brady for the Denver Broncos and Peyton Manning.

It was unfathomable, “a bad, bad decision” according to’s Peter King, particularly after Brady created salary-cap room, presumably for the player he called “the heart and soul” of the team last year, with a contract extension. From King:

The Patriots have made it abundantly clear that only Tom Brady is irreplaceable among players in their world. They’re going to have to figure a way to tell the Irrepleaceable One how they let his favorite weapon get away after Brady did the team such a favor two weeks ago.

New England went out and replaced Welker, who missed only three regular-season games over six years with the Patriots but had big drops in the Super Bowl XLVI loss and in the AFC Championship game loss this year, with Danny Amendola of the St. Louis Rams, who has played in 42 games over his four years in the league. It was a reminder, the Boston Herald’s Ron Borges writes, that something else was going on here.

By every measureable but a calendar (Amendola is 27, Welker 32) paying Danny Amendola more than Wes Welker is ridiculous, but the Patriots value control over all else and thus march to the beat of their own drummer.

Bob Kraft said Monday, his fingers tightly crossed behind his back, that: “I love Wes Welker. I hope he remains a Patriot for life. Just like Tom Brady.”

That was simply nonsense, to be kind. There’s no love between the Patriots and their players. The players are commodities not people, pawns in the game of NFL economics run by guys who aren’t called owners for nothing.

There were reports, as the news broke, that the Irreplaceable One was not happy at losing his favorite target and one of his best friends after his charitable gesture. Brady was described by a source who had had contact with him as “bummed out” (via ESPN Boston’s Mike Reiss). From Yahoo’s Mike Silver:

Either way, the irony can’t be lost on Brady: Manning, the one NFL superstar no one could ever imagine accepting a penny less than market value, will be the guy zipping spirals to the most productive receiver Brady has ever known.

So why, again, did Brady do his bosses a solid by agreeing to that extension?

Brady, who is out of the country and could not be reached for comment, is likely pondering that same question.

Not that Brady hasn’t been through this before, when his friend Lawyer Milloy was released in 2003 and favorite target Deion Branch was traded in 2006. But Bill Belichick, not Brady, makes the personnel decisions and Patriots fans, like Baltimore Ravens fans after the trade of Anquan Boldin and dismantling of the defense, have to trust in past success. From Reiss:

Belichick has never been afraid of making an unpopular move, and his relative success in doing so — and the franchise’s consistent winning ways — has earned him leeway with a passionate fan base that often refers to the motto “In Bill We Trust.”

Yet moving away from the 31-year-old Welker, especially considering the surprisingly low financial terms, could put that to the test. Welker, whom Brady referred to as the “heart and soul” of the team in 2012, was one of the franchise’s most beloved players.

So this qualifies as one of the riskier moves of Belichick’s 13-year tenure, as he replaces a known commodity who was the epitome of reliable and durable with Amendola, a talented player with more long-term upside who has been limited to 12 games over the past two seasons because of injuries.

When it comes to X’s and O’s, part of Belichick’s confidence in taking such a risk is the history of production with slot receivers in the team’s offense. Before Welker, fan favorite Troy Brown also put up big numbers in the slot. It’s no disrespect to Brown and Welker, two talented players, but Belichick has noted that part of the function of New England’s offense sets that position up for big production.

Welker proved that, as no NFL receiver caught more passes over the past six seasons. Now he’ll be catching them in Denver, a surprising turn of events that came down quickly with the door closing even as he gave the team one final chance to sweeten its offer.

Welker ended up taking a little less from the Broncos than Amendola got from the Patriots. Amendola’s deal, according to USA Today’s Jarrett Bell, works out to $6.2 million a year — $200,000 more on average than Welker’s contract. From Bell:

With the less-filling offer the Patriots made to Welker — which some would consider low-ball — Belichick had to know he’d move on to Amendola. Maybe the offer came as it did because, moving forward, Belichick preferred Amendola.

He might have suspected, but couldn’t know for sure, the Broncos would snap up Welker in a heartbeat. Regardless, that was a risk he was willing to take.

Brady will understand — or just deal with it.

No matter how this shakes out for the parties involved, the NFL gets a delicious drama, a new chapter of Brady vs. Manning with the subtext of Welker vs. Amendola and Belichick vs. John Elway. We’ll get an early preview sometime during the regular season: the Broncos will play the Patriots at Gillette Stadium.

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