Hobbled by an unspecified right knee injury, Mavericks’ Luka Doncic clearly hasn’t been his usual dominant self in this first-round playoffs series — not up to his standards in past games against the Clippers, regular-season and playoffs.

After Los Angeles’ 116-111 victory on Sunday afternoon in American Airlines Center, tying the series at 2-2, Doncic’s drop-off is most glaringly reflected in his statistics. He shooting 38.6% from the field, including of 13-of-49 (26.5%) on 3-pointers.

It’s clear Doncic’s defensive falloff since he sustained the knee injury during the first quarter of Game 3. Doncic was whistled for two fouls in the first 2:23 of Game 4 as he struggled to stay in front of Clippers attackers, a pattern that continued through the game as Los Angeles hunted him.

“It’s hurting, obviously, but it shouldn’t be an excuse, man,” Doncic said. “We just came out a little sloppy. We’ve got to do way better than that.”

It might seem like quibbling after a game in which Doncic had a triple-double — 29 points, 10 rebounds and 10 assists. But anyone who has watched Doncic throughout his career, this season especially, knows he isn’t his usual self.

On Sunday he shot 10-of-24 from the field, including 1-of-9 on 3-pointers.

When asked specifically about his ability to move laterally and how that affects his defense, Doncic acknowledged it’s a problem. He was assigned to guard Amir Coffey, but Clippers star James Harden hunted Doncic in pick-and-rolls.

“I mean, yeah, I was in foul trouble,” Doncic said. “We said we wanted to try to limit Harden’s 3s. I was just trying not to give him 3s. Obviously, it wasn’t good, especially me.”

Doncic not being himself is also reflected in his postgame interviews following Games 3 and 4. Doncic’s voice is raspy and he sounds congested. After Game 4, he was asked whether the congestion makes it harder to breathe during games, thus affecting his energy level.

“It’s nothing,” he said. “We lost the game. Like I said before, for the knee, it shouldn’t be an excuse. I’m out there trying to play, trying to play a lot of minutes, trying to play hard. But sometimes you don’t have the perfect situation. So you’ve just got to go through it and do better.”

As Doncic noted, the Mavericks still not only rallied from a 31-point deficit but took a 105-104 lead on Kyrie Irving’s driving layup with 2:15 left. Irving scored 40 points, all of them after the first quarter.

“I have to help him more,” Doncic said. “I feel like I am letting him down so I have to be there. I have to help him more. He’s giving everything that he has. He’s been amazing for us the whole series.”

Twitter: @townbrad

Find more Mavericks coverage from The Dallas Morning News here.