Sam Amick

USA TODAY Sports

Contract extension or no contract extension, Jimmy Butler can still afford a cab ride.

So it was last week in Sacramento, where the Chicago Bulls guard showed up via taxi nearly an hour before any of his teammates would arrive to that morning's shoot-around. So it is and may always be for Butler, the 25-year-old whose extra work is paying off like never before this season — even though he didn't get a new deal done with the Bulls before last month's extension deadline.

Butler swears he's not working any harder now because the Bulls decided against giving him the maximum-salary contract his representatives were seeking. And despite injuries to Derrick Rose and Pau Gasol giving Butler the starring role he's never had before, it's not as though he's only working overtime now because the spotlight is brighter.

This is — to the delight of coach Tom Thibodeau and the rest of this Bulls group that has been trying to take that next step for so many years now — just Jimmy being Jimmy.

The Bulls are going through a brutal early-season road stretch, one that got worse in Friday's loss to the Portland Trail Blazers when super sixth man Taj Gibson sprained his ankle, which could keep him out for a few weeks. If they're going to survive, Butler is going to be leading the way. He's putting up All-Star caliber numbers to this point (20.4 points, 6.2 rebounds, 3.5 assists and 1.5 steals a game) while looking like a front-runner for the league's Most Improved Player Award.

And as anyone who knows his story could imagine, the challenges that surround him hardly qualify as insurmountable considering where Butler has been. Before starring at Marquette and being drafted 30th overall in 2011, the Tomball, Texas, native was homeless at the age of 13 when his mother put him on the street (with his father playing no part in his life), and he later lived with an adopted family.

Butler has long since found his way, and he's convinced the Bulls (8-5) will do just that by the time the end of this season rolls around. When asked last week if this is a championship team, even with the recent rash of injuries, Butler told USA TODAY Sports, "Hell yeah, it's a championship team. We're going to win that (expletive)."

From Thibodeau to Butler to reigning Defensive Player of the Year Joakim Noah on down, there is a contagious confidence with this group that has been serving them so well in these past two tumultuous seasons. But this latest situation with Rose, the one in which his recent comments relating to his hamstring injury have been so widely criticized, is having a hardening effect that Butler says will pull them through.

"Whatever everybody says on the outside we don't pay attention to because we're the ones who have to go out there and win games," Butler said. "It's us against the world. Some people are on our side, and some people aren't. That's how it is.

"We've got a team full of NBA players just like everybody else. One guy goes down, and the next has to step up and produce. Don't get me wrong. I don't want anybody to get hurt, but we still have a team full of good guys and we can still win games… We're a good team. We play hard. You know, everything doesn't go your way, but we can only control the things that we can control."

Like Noah before him, Butler said people need to relax when it comes to criticizing Rose.

"Man, (Rose's) head is in the same place all of our heads are in, and that's wanting to win a championship," Butler said. "That's what he's getting ready for. That's what we're getting ready for. We want him to be 100% — not 99% — because you come back too early and you're risking another injury. He's fine. He's our leader, and he knows what he's doing."

As for Butler's mindset after not getting an extension deal done with the Bulls, he shook his head when asked if there's any lingering resentment.

"Nah, nah," said Butler, who will be a restricted free agent next summer. "I love the city of Chicago. I think everybody knows that. I just feel like I've just got to help win games, man. I want a championship. The money has never been an issue because I'm from Tomball. The money I make now is more than nothing. I just wanted to prove to my teammates, to my coaches, to the city, that I'm here to stay."