Basketball isn’t a complicated game. It’s easy to forget that when you think about the Sixers. The sum of their parts says that they are a legitimate NBA contender. Yet the sum of their 70 games says they aren’t. And so you rack your brain for theories that might explain the disparity. A lack of discipline on the part of the stars. A lack of aptitude on the part of the coach. Eventually, you sigh and declare them an enigma. The Sixers are a team that just can’t be figured out.

Except, they really aren’t a mystery. They’re just woefully deficient in one of the fundamental skills of the game that they play. This was obvious on Sunday night, because it was one of the few nights where this fundamental skill was on display. They had the Trail Blazers on the ropes, and they had them there because Josh Richardson and Alec Burks did what game-changing basketball players have done since the sport’s inception. They created shooting opportunities for themselves, and they converted their shots.

In the end, Damian Lillard and C.J. McCollum did it better, and the Blazers escaped with a 124-121 win. But that only underscores the point. Basketball is a sport in which it is much easier to defend a player who is stationary than one who is moving with his dribble. The better a player moves off of his dribble, the more difficult he is to defend, and the space he creates for himself or for others. The better teams in the NBA tend to have at least one player who is in the upper echelon in this skill.

If all of that sounds like a kindergarten gym teacher’s explanation of the sport, therein lies the point. We’ve spent months wondering why the Sixers seem to lack the dynamism you’d expect out of an NBA contender. But maybe it’s as simple as the fact that they lack the game’s most dynamic type of player.

On Sunday night, you saw what can happen when a team has a player who can break down a defense without any more help than a basic ball screen. The Sixers had two of them at varying points. Down by as many as 17 points in the first half, they somehow held a lead in the fourth quarter and had a chance to tie it at the buzzer. This, despite playing most of the game without their two biggest stars, with Joel Embiid suffering an ankle injury in the first half and joining Ben Simmons on the injured list.

They did it because of Josh Richardson and Alec Burks, both of whom took the ball in their hands and put opposing defenders on their heels. Richardson was the undisputed star, scoring 34 points on 13-of-20 shooting and hitting six of his 10 three-point attempts. Whether he was pulling up from behind the arc or getting into the paint and dishing to Al Horford, Richardson showed just how different the Sixers can look when they get dynamic guard play.

Likewise with Burks. Unlike Richardson, his game has long been predicated on his ability to create shots for himself. The quality of those shots, and the rate at which he converts them, has always been the issue. Sunday was one of his good nights, and you saw how big of an impact it can have on the game. With Richardson on the bench early in the fourth quarter, he beat a defender off the dribble and knifed through the lane for a reverse layup. Later in the quarter, he got to a spot on the baseline and hit a fadeaway jumper. He finished with 20 points on 8-of-14 shooting.

Of course, neither performance came close to equaling the one that Portland got from Lillard, who became the second player to go for 50-plus against the Sixers since they entered the Disney bubble.

“I think when you study the most dangerous offensive players in our sport, and if you study the emergence of what I’m about to say, there is zero doubt that the most difficult people to defend are the live-ball guards,” Sixers coach Brett Brown said.

Granted, the Sixers aren’t built like the Blazers. But maybe that’s part of the problem — not that they lack a Damian Lillard, but that they lack a player who can do what Richardson and Burks did against the Blazers more frequently. Heading into the season, the hope was that Richardson would be that player, but he isn’t an elite ballhandler, and he does not regularly score with the efficiency that we saw out of him on Sunday. Aside from occasional flashes from Burks, the Sixers don’t have anybody else. Even when healthy, Simmons has yet to show a consistent ability to win possessions the way elite scorers do. And he simply isn’t a break-you-down ballhandler.

With the playoffs fast approaching, the Sixers need somebody to emerge who can consistently do the sorts of things that you saw out of Richardson and Burks on Sunday night, the sorts of things that Jimmy Butler did with his combination of strength and slashing ability last postseason. If they can’t stop the Lillards of the world, they are going to have to score with them. Richardson gave them his best effort against Portland. Now, they need it more often.