Last night Jimmy Butler became one of only four Bulls to have scored 50 points in a game. (He joins Chet Walker and Jamal Crawford, who each did it once, and Michael Jordan, who  did it an incredible 30 times, plus another eight in the playoffs).

After Thursday’s game, a 115-111 victory over Philadelphia, the Elias Sports Bureau got a lot of stat questions about the Bulls, especially Jimmy Buckets. This was pretty remarkable:

Q: Jimmy Butler made 21 free throws on Thursday. Who was the last Bulls player with that many free throws made in a game

A: Michael Jordan, who made 22 on April 18, 1998, against New York.

That's a lot of free throws. It was an overtime game, but that's about how many free throws the league-leading Timberwolves make on an average night. And it highlights something interesting about Jimmy Butler's rise.

Butler is increasingly becoming the focus of the Bulls offense, as his usage stats suggest. Usage is pretty simple: it's basically the percentage of a team's plays in which a player attempts a shot, free throw, or makes a turnover. Butler's usage percentage is going up; here are his numbers for the first three months of this season and the last (not including the three games in October of this year).

Butler’s usage percentage is at 25.0 percent for the season and rising, but it’s still below Derrick Rose’s 25.5 percent. Furthermore, among the Bulls' regulars, Butler takes just the fourth-highest percentage of shots the team takes when he's on the court, behind Rose, Pau Gasol, and Aaron Brooks.

So how is he leading the Bulls in scoring? Butler's crazy number of free throws last night reflect part of the puzzle. When Butler is on the court, here's the percentage of the team's free throws that he's taken, again through the first three months of the season.

This season, Butler has taken 42 percent of the Bulls free throws attempted while he's on the court. And that's a dominant number. For comparison, Butler has taken only 24.1 percent of the Bulls' field-goal attempts when he's on the court, which ranks a mere 60th in the NBA for players who have played at least 400 minutes this year.

But among that same cohort, 42 percent of free-throws attempted ranks third, behind DeMarcus Cousins and James Harden, who are not merely stars but far and away the dominant players on their teams. Fourth, behind Butler, is Russell Westbrook, one half of Oklahoma City's superstar duo. (Butler also ranks just behind Westbrook, among guards, for most field goals made per game within five feet of the basket.)

It also helps that once Butler gets to the line, he proceeds makes 83.4 percent of his shots, the third-highest percentage on the team.

Getting fouled is a skill; and as Butler’s game develops, it looks like something he can do at an elite level.