Rose, 30, twice used the phrase when asked how he would move forward without coach Tom Thibodeau, who was fired Sunday.
"I have a lot of confidence in myself," Rose said Monday. "Thibs was just the coach that believed in me. I mean, he jump-started my career again and for that, I'll always be thankful. But everybody that thinks that it's gonna stop, kill yourself. It's just not."
Rose later tweeted an apology, saying he meant it as a "slang term" rather than an instruction for people to harm themselves.
I messed up by using the slang term "kill yourself" today in response to a question about whether I can continue to perform without coach Thibs. I did not mean it literally and regret using it so I apologize.— Derrick Rose (@drose) January 7, 2019
Rose was clearly smarting over the departure of Thibodeau, who had coached him in both Chicago and Minneapolis. Under Thibodeau, Rose was a three-time All-Star in Chicago and was the league's MVP in 2011 before enduring multiple season-ending knee surgeries.
This season, Rose has resurrected his career, averaging 18.9 points and 4.8 assists per game while shooting a career-high 46.2 percent from 3-point range. His unexpected return to form produced a 50-point game on Halloween, and Rose has his highest scoring average and Player Efficiency Rating since the 2011-12 season.
That resurgence, Rose said, wouldn't have been possible without Thibodeau. But as he recalled some down moments prior to joining Minnesota last season, Rose again used the "kill yourself" term, which many found insensitive.
"He was the only coach that believed in me," Rose said. "Right when I got the call, I was in Cleveland practicing at Cleveland State, by myself, with me and my little guy Art. It was me and him in the gym, by ourselves, five days a week.
"I had a kid at that time, my baby girl. And no teams wasn't looking for me at all. I was basically out of the league. And even coming here, everybody didn't know I was gonna play this way. Like, [Thibodeau] believed me. I believed in myself. My family believed in me. And my little guy Art believed in me. And we got it done. But like I said, think that I'm not gonna play the same way, kill yourself, because I believe in myself."