Jason Thompson's left knee has been sore. He has been in foul trouble, and his rebounding numbers have taken a serious dip.
Meanwhile, Thompson's backup, rookie Thomas Robinson, seems to be finding his groove.
In Thompson's past 13 games, he's averaging 4.6 rebounds, with his last double-digit rebounding game coming Jan. 2 at Cleveland.
Over that span, Robinson is averaging 5.8 rebounds in 15 minutes per game compared with 24.9 minutes for Thompson.
"I think (Thompson is) a little nicked up, so that kind of plays a part into his production," said Kings coach Keith Smart, whose team has passed the midway point of the season. "And then (there have been) some foul trouble situations. But (Robinson) is playing hard, coming along every day, and you want to have that on your team."
Thompson said he needs to be more aggressive on offense to rediscover his rhythm.
He has taken to overpassing, which, coupled with foul trouble, has slowed him down, he said.
Thompson said Robinson's presence isn't putting more pressure on him to perform.
"I don't think so," Thompson said. "It's good that Thomas is playing well. He's our first-round draft pick, and we expect him to play well. So it's good that he has, and I'll just go back to my ways. (I) know what I can do."
The Kings have been outrebounded 27 times in 43 games.
Robinson has four double-digit rebounding games this month, including a career-best 14 in Wednesday's loss to Phoenix.
Thompson's rebounding average in 13 games this month is 2.3 per game less than his season average.
Robinson's average in January is 1.2 rebounds better than his season average.
"Rebounding is desire and effort, and (Thompson has) got to find that again," Smart said. "(It's) to be able to get to the glass and be relentless where someone can't keep you from grabbing a rebound. That's what Thomas has done the last couple of games and (DeMarcus Cousins) has been doing all (season), but that's what Jason has to get back to."
Robinson said his focus has been simple: "Chasing literally everything down that I can try to get my hands on."
Robinson's play has been what the Kings have wanted all season, though he admittedly fought the role. He might be the most athletic King and plays with great energy.
"The game is slowing down a little bit for him, and he's slowing down, which is making him faster so he can utilize (his skills)," Smart said.
Smart said matchups still might dictate playing time for Thompson or Robinson.
Smart said if tonight's opponent, the Oklahoma City Thunder, uses All-Star Kevin Durant at power forward, a perimeter-based player might be needed to match up.
But at this stage of his rookie campaign, Robinson believes he's playing the way he had hoped in the NBA.
"I feel like I'm just playing basketball," Robinson said. "Like it's nothing too complicated."