Chris Paul had already started the fourth quarter by draining a long 3-pointer and passing to Cameron Johnson, his Phoenix Suns teammate, for another. It was a bad sign for the visiting Dallas Mavericks, because Paul hadn't even called for the defensive matchup he really wanted.

His next time up the court, Paul was dribbling against Reggie Bullock when Johnson set a high screen on Bullock, dragging his defender with him. That defender was Luka Doncic, who found himself guarding Paul after the switch — and even managed to poke the ball away. But after Paul regained possession, he needed about 3 nanoseconds to blow past Doncic for a layup.

It was the sort of scene that kept repeating itself in the closing stages of the Suns’ 129-109 victory in Game 2 of their Western Conference semifinal series on Wednesday. The Suns were determined to force Doncic onto the ball, and then they were eager to capitalize. Doncic, who has the meaty build of a tight end at 6-foot-7 and 230 pounds, is an all-world offensive player. But his defense? For one game, at least, he went from hunter to hunted against shifty guards like Paul and Devin Booker.

“Just have to play better defense,” Doncic said, “that’s it.”

No one has been surprised to see two point guards take center stage in this series, which the Suns lead, 2-0, as it heads to Dallas for Game 3 on Friday. But in the process, Paul and Doncic have offered contrasting approaches. Paul has picked his moments to take charge, a luxury given the talent that surrounds him, while Doncic has tried to do it all, in large part because he has no choice.

“We believe, man,” Doncic said, adding: “We’re going to believe until the end.”

Doncic has been putting up preposterous numbers, even by his gaudy standards. In Game 1, he finished with 45 points, 12 rebounds and 8 assists. In Game 2, he had 35 points, 5 rebounds and 7 assists. Mavericks Coach Jason Kidd put the pressure on Doncic’s supporting cast to assert itself in Game 3.

“He had a great game,” Kidd said of Doncic, “but no one else showed. So we’ve got to get the other guys shooting the ball better. We can’t win with just him out there scoring 30 a night, not at this time of year.”

For Paul, the playoffs are another opportunity — arguably his best one yet — to win his first championship, one season after the Suns fell to the Milwaukee Bucks in the N.B.A. finals. Phoenix, Booker said, is on a “revenge tour,” which Paul seems to be steering from his personal time machine. Paul finished with 28 points and 8 assists on Wednesday, a tour de force two days before his 37th birthday.

“He can tell you better than I can,” Booker said, “but he’s feeling younger by the day.”

In his own way, given his size and approach, Paul is unapologetically old school. Growing up in North Carolina, he was the prototypical point guard: a dazzling scorer, to be sure, but someone who was responsible, first and foremost, for involving teammates. Now, he has the institutional knowledge of 17 N.B.A. seasons informing each of his decisions.

Doncic, on the other hand, is one of the league’s new-age players, a 23-year-old prodigy with a multidimensional game that was informed by his childhood in Slovenia, where children, no matter how big or how small, learned the fundamentals of shooting and passing.

In this playoff series, the throwback has the edge. It helps, of course, that the Suns are a deeper team and that Paul plays alongside Booker, a three-time All-Star and one of the league’s most gifted scorers.

For three quarters of Wednesday’s game, Paul largely created for his teammates, attempting just nine shots. He exploded in the fourth quarter, scoring 14 points while shooting 6 of 7 from the field.

“It’s amazing,” the Suns’ Jae Crowder said. “For the first two quarters, he’s relaxed, chilling. He’s not too aggressive, just reading the game. And then he has a switch where he just turns it on.”

Booker, 25, thought back to his childhood when he would watch games with his father, Melvin Booker, a former N.B.A. guard who shaped his son through daily workouts. In front of the TV, they would study Paul together. Devin was 5 years old, he said, exaggerating modestly.

“See how he makes sure everyone’s involved?” Booker recalled his father asking him. “And then he picks his times when he’s going to take over the game?”

Booker added: “I’ve always admired the way he does that. He’s just in control at all times. He’s two, three steps ahead of what the other team is doing.”

As Paul surged in the fourth quarter, Doncic, having already carried such an enormous load for his team, seemed to tire — especially on defense. Kidd said he would need to concoct a plan to ensure that Doncic’s teammates “do a better job of helping him.” Perhaps the Mavericks need to avoid switching on screens so frequently, or perhaps they need to send more double-teams at Booker and Paul. Easier said than done.

Paul joined Booker at his postgame news conference in time to answer a question about the importance of making Doncic work at both ends. Booker glanced at Paul and seemed to smirk, as if to say they had done their job picking him apart. Paul, forever the cagey veteran, chose the diplomatic route.

“We just try to play,” he said. “Take what the defense gives us.”

It was an exhausting night for Doncic. As he made his way off the court at halftime, he wheeled around to bark at a heckler.

“He was just saying something reckless,” Doncic said. “If it’s something normal, I would not even look because I don’t care. But sometimes you’re in a bad mood and they say some bad stuff. It’s normal. We’re people, man. It’s normal to turn around.”

Ahead of Game 3, Doncic had a chance to plot some revenge of his own.