By my estimation, John Elway loves two things above all else.

Winning and a challenge.

And by that same estimation, he hates losing more than losing a coach – even one that he deeply respects and appreciates. Gary Kubiak was that coach.

On Monday, as Elway said goodbye to the coach who masterfully won him another Super Bowl, this time as a sometimes ruthless executive, he did so with – as Elway put it himself – “mixed emotions.”

It was a sad day, because the Broncos were saying goodbye to one of their own, one of their very best. And not because he was riding off into the sunset, a privilege that Elway of all people, can appreciate.

It was, as I imagine for Elway, a happy day in that he and Kubiak depart as they’ve always been – as friends.

“When [Gary] said, ‘I want to talk to you as a friend,’” Elway recounted before introducing his soon-to-be former head coach, “Gary personally became the priority.”

I believe that. There was a sincerity in Elway’s words; his stories were told from the heart, not the way in which he “thanked” John Fox.

Make no mistake, Elway and Kubiak were, are and will remain friends. There has been much speculation about whether there was a budding riff between coach and GM, whether impending coaching staff changes were coming down the pike, whether an extremely loyal Kubiak would be okay with that, whether the two agreed on the future of the quarterback position. Perhaps there’s even a fraction of truth to some or all of that, but the way these two guys talked about and to each other Monday, whatever “riff” might or might not be there, was anything but insurmountable.

The funny thing, at least in professional football, is that a parting of the ways – even between friends – is inevitable. How that parting goes generally puts even the greatest of friendships to the test. The circumstances surrounding Kubiak’s decision to walk away, while unfortunate, eliminate the chance of an ugly parting.

On a personal level, Elway might indeed be saddened. But professionally? There was a gleam in Elway’s eyes that looked more like competitive fire than the pain that comes with being slugged in the gut.

“I’m sure John is unhappy that his good friend and head coach Gary Kubiak is leaving, but I would also bet that John sees this as an opportunity,” Les Shapiro, who has covered Elway for many, many years told me. “John like challenges. John is entrepreneurial. John likes to build things. And now, in some respects, he gets to build the Broncos once again.”

Building the Broncos, a team already possessing a championship-caliber defense, might only require some tinkering. Regardless, they won’t be winning back-to-back Super Bowls this February. Elway has got to love that challenge.

It’s not as if Kubiak couldn’t have helped Elway win another one. That ship would have sailed for at least a season or two more. Kubiak guided the Broncos to a title; that’s worth a lot, even to someone who is impatiently fanatical about winning as Elway.

Elway gave Kubiak the only head coaching job he would have ever considered at this stage in his life.

Kubiak gave Elway the only thing that’s ever mattered to him as a professional.

And now, Kubiak gives Elway another chance at the only thing he likes as much as winning: Building a winner.

By nearly every account, this was a perfect ending.