Bobby Portis' first crack at playing major minutes this season was by chance. The Chicago Bulls had played four overtimes against the Detroit Pistons one night in December and had a game in New York the next. They left Pau Gasol at home to rest, which opened up minutes for the rookie, and Portis responded with a 20-point, 11-rebound performance in just 23 minutes against the New York Knicks.
Since then, it's been a roller-coaster ride for Portis, who has been forced into a bigger role than anticipated as injuries have wiped out Chicago's frontcourt depth. With Joakim Noah out for the season with a shoulder injury and Nikola Mirotic out through the All-Star break after undergoing an appendectomy, head coach Fred Hoiberg has been forced to lean on Portis far more than he thought he would.
The results have been mixed.
The Bulls are 10.1 points per 100 possessions worse when Portis is on the floor than when he's on the bench, per NBA.com.
It's about what you'd expect would happen when an inexperienced player starts playing major minutes on a team filled with veteran depth and big names. At first, he comes out of nowhere and takes opponents by surprise. Then, once he gets added to the scouting report, there's an adjustment period.
"Obviously you get a better feel for guys when they're in a regular rotation than when they're just playing spot minutes early on," Hoiberg said after a January practice. "I guess you kind of go back to the college scouts and ask them what the kid was like at Arkansas. So now that he's got some consistent minutes, teams are going to play him a little bit differently than initially."
That's where Portis has been since a promising early stretch. His field-goal percentage dropped from 48.4 percent in December to 39.8 percent in January, and his minutes have fluctuated.
Out of the 10 contests before the seven-game road trip Chicago started last week, Portis' minutes were in the single digits seven times. Since January 1, he's only scored in double figures once, when he had 16 points in a Jan. 20 blowout loss to the Golden State Warriors.
With the injuries to Noah and Mirotic, Portis will have an opportunity for more consistent burn, whether he's ready for it or not. The Bulls' only other healthy big men are Taj Gibson and Pau Gasol, the latter of whom can't be expected to play a heavy nightly schedule at 35 years old.
The circumstances will call for Portis to see the floor more often, and despite his recent struggles, the Bulls are optimistic he'll improve over time.
"Obviously, Bobby's going to play a big part in what we've got for the rest of the season," Hoiberg said. "The big thing is just going out and doing what he did, playing hard and throwing his body around. Rebounding the ball, defending and making shots. And we're confident Bobby will do that."
Although he's been getting more run, his place in the rotation has been in flux. The most used lineup with Portis in it—a unit that also features Cameron Bairstow, Tony Snell, Doug McDermott and E'Twaun Moore—has played just over 20 minutes together, according to Basketball-Reference.com.
Portis' work ethic has been the constant. Hoiberg raves about his approach in practice, as have his teammates. 'Maturity' was one of the reasons it was such a surprise when he fell to the Bulls at No. 22 last June.
"He studies the film," Jimmy Butler said last month. "He's always out there working on his game. We've been telling him all along his time is going to come. Obviously, we never wanted it to come when somebody is injured. But eventually he was going to get his time to shine and show what he can really do.
"I think he's ready. If he continues to work, he can be really good. He's really good right now. But you can't settle. You always have to want to get better. I haven't seen him settling out here. He's always working on his game and asking questions. There's a lot of potential. He's going to be a really good player."
It's reasonable to expect that increased minutes will breed increased confidence and consistency for the rookie. Hoiberg has thus far shown a willingness to let his youngsters play through mistakes in his first season as Bulls coach, and growth will follow experience.
A lot of Portis' struggles are normal rookie growing pains. There's still every reason to believe he's going to be a productive rotation player for years to come, maybe even a starter.
But for now, his missteps will be amplified on his way into a bigger role than anyone planned on him having this early on.