Conventional wisdom argued that the Portland Trailblazers, in order to progress as a team, simply couldn't keep both C.J. McCollum and Damian Lillard.

A team built around two point guards -- both with similar strengths to their games -- simply couldn't form the foundation of a winning team. And the more McCollum developed offensively, the less the Portland attack could sustain itself and find opportunities for both of them. And together, the two of them would individually stagnate.

The Blazers took a different view, signing McCollum to a four-year, $106 million contract extension this summer, while coach Terry Stotts has increased the number of minutes per game the pair spends on the court together this season. 

The result has been a blurring of the very definition of point guard. Remarkably, neither Lillard nor McCollum leads the team in assist percentage -- that honor belongs to big man Mason Plumlee.

But both McCollum and Lillard are better than they've ever been, and a Blazers team that simply hasn't defended or rebounded so far still is hanging in there at 9-10.

"I think they've both done a good job of expanding their offensive game," Stotts said last week. "Dame's floater has obviously improved over the course of his time in the NBA, and his finishing has improved. C.J. showed last year, his ballhandling and getting around screens. As talented as they are, they have improved, and I know they're going to continue to evolve. How much, only time will tell."

For Lillard, the tangible benefits of the added floater have been enormous. Lillard's true shooting percentage has jumped from 56 percent last year to 61 percent this season, and it is powered in large part by his accuracy from 0-3 feet improving from 54.6 percent last year to 62.4 percent this year. He's taking more of those shots around the rim as well, a shift in his game that he planned out last summer, when he said he'd make 800 shots, sometimes even 1,000, in a day of practice.

"Guys are big down there," Lillard said. "You get your shot blocked. The year before last, I got my shot blocked more than any other point guard, because I like to get to the rim. And challenging those guys is tough. They're seven-feet, their timing is great, they're athletic. So I've just tried to figure out more crafty ways to take advantage of getting into the paint. From time-to-time, it's okay to challenge them. But the floater? That's a giant-killer. They can't touch you, go into your body, and they can't go way up there and get it."

They aren't. And while Lillard's usage is up to 32 percent this year -- a career-high -- he's more efficient than ever before.

The collective statline simply reinforces in Lillard's mind something he's believed from the start: He belongs in the conversation for the best point guard in the league, even if he shares the title on his own team.

"I've always believed I can compete with the really high level point guards, even as a rookie," Lillard said. "When I competed with Russ [Westbrook], CP, Steph and those guys, they were a lot better than me. But I felt like, when I got out on that court, I could compete with them. Obviously, over time, I've gotten better. So now, I feel like I'm in that group."

And McCollum isn't suffering for it. He now has the second highest usage rate of his career, at 26.8 percent, while his true shooting percentage elevated to 58.6 percent this year from 54.4 percent last season. His shooting prowess is up across the spectrum, notably both from 3-10 and 10-16 feet, while his 44.5 percent from three-point range is also a career-high.

"It says a lot about the structure of our offense," McCollum said. "There's a lot of continuity and flow in our offense. Coming off pin-downs, handoffs, staggers. Provides a lot of scoring prowess for our team, and takes a lot of energy."

About that energy: Playing McCollum and Lillard together for roughly half the game, and asking them to do virtually everything at both ends, has led to a remarkable bit of travel time already -- they're ranked 1-2 in miles run in the league this year, which is even more astonishing when you consider the Blazers as a team are just ninth in the league in pace.

There is a price to pay for that, at least so far. Both Lillard and McCollum have seen declines in their defensive numbers, whether measured by defensive win shares or Defensive Plus/Minus. The Blazers as a whole are 30th in defensive efficiency, after finishing at a more respectable 20th last year.

For his part, Stotts doesn't believe the extent to which he's maxing out his amazing backcourt necessarily means there needs to be a tradeoff, or that he should ask less of his duo on the defensive end in response.

"It's still a team thing," Stotts said. "Everybody has responsibility, no matter what they're doing at the offensive end. The big guys obviously have to protect the rim, protect on pick-and-rolls, but the guards, regardless of what they do at the offensive end."

How the Blazers will leverage the performances of Lillard and McCollum will have everything to do with how much they can improve on the defensive end, particularly rebounding, and if the pair can continue to play at this unstoppable pace.

But regardless of wins and losses, McCollum and Lillard are more than just co-existing. They have a strong case to make as the very best backcourt in the league -- even in a league where Steph Curry and Klay Thompson reside.

Plumlee, for his part, did not hesitate when asked if he played with the best backcourt in the NBA. Stotts demurred, saying, "I don't rank them. We've got one of the best, put it that way."

And Lillard acknowledged that even now, the pair of unheralded programs which produced these two -- Weber State for Lillard, Lehigh for McCollum -- may be keeping the world from fully appreciating just how good they've become.

"At this point, the lack of recognition, it is what it is," Lillard said. "There could be a lot of reasons for it. We've decided to go out on the court and do what we're going to do. Anything that we feel, we have to say, we keep it to ourselves, and go out and prove it. Like you said, the numbers speak for themselves. We'd like for those numbers to translate to more wins. But I think our backcourt is up there with anybody."

And so: Which one is the point guard? The question itself has ceased to matter. Stotts said he doesn't have one point guard when they both play, but rather, "the luxury of two point guards, two shooting guards at the same time." For Lillard, it is about "being a servant to others, something I have no problem doing."

But the man at the center of all the action, all the running, the leader in assist percentage himself, explained it this way: "I don't even think you declare positions so much as you put out a bunch of players and go play," Plumlee said. "Some teams, there's no seven-footers. Some teams you have a big guy in there. Whether they're point guards, shooting guards, whatever, they're a problem when they come out there. That's the bigger thing."