HOUSTON -- Chicago Bulls All-Star swingman Jimmy Butler sat out Friday's 121-117 loss to the Houston Rockets because of a right heel contusion. An MRI is scheduled for Saturday.

Michael Carter-Williams started in Butler's place and had 23 points, nine rebounds and six assists before fouling out with two minutes left in overtime.

Butler did not sound worried about the injury after Friday's game, but he will need more tests to determine if he will miss any more games.

"He went out there, he was having trouble putting pressure on that foot," Bulls head coach Fred Hoiberg said. "So we decided to play it safe and sit him tonight."

It is unclear exactly when Butler's injury occurred, but he was wearing an ice pack around his right foot after Wednesday's game against the Oklahoma City Thunder.

The Bulls' Jimmy Butler will undergo an MRI on his right heel on Saturday to determine if he'll need to sit out any more games. Layne Murdoch/NBAE/Getty Images

Bulls guard Dwyane Wade acknowledged that some of his teammates didn't even know Butler wasn't playing until just before the game.

"I knew because I was on Twitter before I came in here," Wade said. "I was getting my massage, and I was reading Twitter, and I saw [media] tweeting that Jimmy wasn't playing. ... One of y'all tweeted that coach [Hoiberg] said the lineup was good, Mike [Carter-Williams] might play, and the next thing you know, Jimmy's out. I was like, 'OK.' I appreciate you guys.

"Coach said, 'Mike, you got James [Harden],' and everybody's like, 'What?' But that's what happens. Everyone knows that [Butler] took a tough one in OKC, and you got to be ready. Everyone went over the plays, everyone knew how to guard the sets early in shootaround, so guys were ready."

Friday marked the third game Butler has missed this season. He missed two games last month because of flu-like symptoms. Butler is averaging 24.6 points, 6.5 rebounds and 4.8 assists per game.

Hoiberg said he is hopeful that Butler will start feeling better in the next few days. The Bulls continue their six-game road trip on Monday with a game against the Sacramento Kings.

"We'll see," Hoiberg said. "We'll see how he is tomorrow. Hopefully he makes progress over the next two days and we'll make the determination, probably game-time [decision] before Sacramento [on Monday]."