Memphis star Ja Morant and Miami's Tyler Herro, two of the NBA's top young guards, delivered dazzling performances on Thursday in impressive triumphs.

Morant had a triple double for the host Grizzlies, who stretched their win streak to seven games and overtook New Orleans for the Western Conference lead, while Herro unleashed a historic career-best effort for the Heat.

Morant managed his third triple double of the season and the seventh of his career with 25 points, 10 rebounds and 10 assists to lead Memphis in a 142-101 rout over Milwaukee.

Asked if it was the Grizzlies' best performance so far this season, Morant said: "Easily."

The 23-year-old guard's masterful display highlighted a blowout triumph for Memphis, which led 70-41 at half-time and 117-71 after three quarters.

"We were real locked in on the defensive end and that got us easy looks," Morant said. "We were able to get out and run, get inside the paint and score there."

Herro scored a career-high 41 points, making 13-of-20 shots from the floor and 10-of-15 from three-point range, and added six rebounds for the Heat in a 111-108 victory at Houston.

The 22-year-old guard became the youngest NBA player to produce 40 points, 10 three-pointers and five rebounds in the same game.

"I'm feeling good, just trying to get good looks, get the ball up and not pass up my open ones," Herro said. "My teammates get me the ball in situations where I can make a play and it's another great win."