When the Bulls resume practice Monday afternoon, positions will be up for grabs. Bulls coach Fred Hoiberg deemed it so.

Fuming following Saturday’s forgettable 32-point home thrashing at the hands of the Thunder, Hoiberg vowed to put his team through its most grueling practices of the year Monday and Tuesday, and said this week could redefine roles.

“It’s open right now,” Hoiberg said. “We’re going to go in and compete and see who wants to play.”

Veteran center Robin Lopez was the only lock as a starter entering training camp, Hoiberg said recently. Promising rookie Lauri Markkanen has no need to look over his shoulder — and shouldn’t even when (if?) Bobby Portis and Nikola Mirotic return. Shooting guard Justin Holiday figures to be secure for however long Zach LaVine is rehabbing. Small forward Paul Zipser has been underwhelming and could be replaced, although his perimeter shooting may afford him more time.

That means no starting spot is more tenuous than point guard. Jerian Grant has been erratic through five games, averaging nine points, 3.6 rebounds and 6.6 assists with shooting splits of .333/.063/.778. Meanwhile, Kris Dunn added another dimension in his Bulls debut Saturday. Despite showing clear signs of rust in his first game action since sustaining a dislocated left index finger on Oct. 6, Dunn had an eventful evening, scoring eight points with four rebounds, three assists, three steals, one blocked shot, four turnovers and five fouls in 22 minutes.

In the season opener at Toronto, Hoiberg didn’t hesitate to slide Kay Felder into the primary backup point guard role over Ryan Arcidiacono to start the second half. On Saturday, we saw Hoiberg shorten Grant’s leash, playing him with the first string for only the first 5 1/2 minutes of the second half. In that span, Grant went scoreless while posting a pedestrian one assist, one rebound and one foul.

By the time the Bulls take the court Wednesday night at Miami, starting point guard duty might belong to Dunn.

“I love to compete,” Dunn said. “I’m not trying to go for the starting spot, but it’s definitely a dream of mine to start for an organization. So I’m definitely going to compete.”

Here’s a look at why Hoiberg might soon decide to start Dunn.

On-ball defense

Dunn’s biggest strength at this stage in his career is his ability to pressure his man and cause chaos. “Kris, at times, has shown that he can be a lockdown defender,” Hoiberg said. The Bulls currently lack that ingredient and sorely need it. Outside of Dunn, their best perimeter pests are Felder and David Nwaba, role players who are both limited for different reasons. It’s no coincidence that Chicago ranks last in forcing turnovers (11.6 per game) and second-to-last in steals (5.4 per game).

As shown in the below clip, Grant’s ball pressure is weak. He supplies token defense to keep his man in front, but in the process he allows Russell Westbrook time and space to comfortably survey the floor and settle on a decision. There’s no disruption to the start of the Thunder’s offense. Once Westbrook has his play, a high ball screen with Steven Adams, set up, Grant jogs gingerly over the screen, leaving Lopez in the unenviable position of stopping a charging Westbrook. Worse, Grant is slow to rotate to Adams and block Westbrook’s wide open pocket pass. The result is an easy dunk.

In this clip, Grant is again supplying token defense. And, again, it’s allowing Westbrook to survey the court. This time, Adams doesn’t come up to set a screen on Grant. He instead seals Lopez so that Westbrook has a clear path to the basket. As Grant plays off, Westbrook is just patiently waiting for the green light from Adams. When Westbrook turns on the jets, Grant doesn’t have the foot speed to keep up (few do). It results in another easy shot at the rim.

Now compare that to Dunn’s on-ball defense.

The difference is night and day. Dunn plays much closer to the ball-handler — even the lightning quick Westbrook — and moves his feet exceptionally well to prevent two attempts by Westbrook to get into the paint. Dunn’s frame also allows him to be more physical, which makes it difficult for offensive players to bump him off his spot and helps him fight over screens. Notice the effort Dunn gives to get back into the play after Adams comes up to set a screen. Although Dunn didn’t force the turnover on this possession, his second effort on subsequent trips routinely blew up the Thunder’s offense.

Below is another look at Dunn’s ball pressure. Perhaps knowing he’s now the superior athlete in this matchup, Dunn was a little over-aggressive against Raymond Felton on this possession and got whistled for a foul. It was the first of Dunn’s three fouls in five minutes. It’s an easily avoidable foul, but Dunn’s intensity and unwillingness to back down defensively will make him susceptible to occasional whistles. It beats the alternative of allowing ball-handlers to be comfortable and play in a rhythm all night.

Below, the Thunder are looking for a 2-for-1 opportunity at the end of the first quarter. Dunn, however, destroys their chance. It starts with his ball pressure at halfcourt. Dunn fights over a subtle pick by Carmelo Anthony, which gave Felton just enough space to accelerate toward the paint. But Dunn has the foot speed to get back in the play and poke the ball away from behind. In the third quarter, Dunn did it again. His second effort after being screened by Adams allowed him to get right back in the play and come away with another steal.

Here, Dunn blankets Felton on this entire possession. As Felton works off the ball, running around a screen, setting a screen and running off another screen, Dunn sticks to him the whole way. As Felton tries to receive the ball back at the top of the key, Dunn jumps the passing lane and darts the other way for an uncontested layup. These are the types of steals and breakaway buckets the Bulls haven’t produced consistently. Dunn is likely to change that.

On this last play, Dunn first stops Westbrook in transition, a victory in and of itself. Then, with help from Denzel Valentine, Dunn thwarts Westbrook’s drive to the basket. When Westbrook sucks the defense in, he finds a wide open Jerami Grant and hits him with a pinpoint over-the-head pass. The ultra-athletic Jerami Grant typically would finish the play with a highlight dunk. But Dunn again recovers and swats him on the way up. The Thunder went on to score anyway, but Dunn’s ball pressure, foot speed, second effort and overall intensity on defense make him ideal for helping the Bulls keep points off the board. And with an offense that’s struggling mightily to score (the Bulls are averaging a league-worst 91 points per 100 possessions), every stop counts.

Playmaking

Jerian Grant hasn’t been bad as the starting point guard. He’s been wildly inconsistent, often from one half to the next, but he ranks 13th in assists per game and 12th in assist-to-turnover ratio (3.30). The problem is Grant has been much more of a distributor than a playmaker. He’s spent these first five games making the routine play — a pick-and-pop here, a screen-and-roll pass there. He’s executed fairly well on set plays and looks comfortable making the extra pass when appropriate. While his raw stats look decent, Grant’s not doing anything special in the way of generating offense or getting his teammates open shots.

The Bulls can be much better, which is where Dunn comes in. Unlike Grant, who thrives on predetermined plays, Dunn is more adept at orchestrating plays.

“I like this offense. It’s a lot of spacing, a lot of shooting around me,” Dunn said. “So I try to get downhill and try to create for my guys. Once they hit shots it creates for me. So I definitely like this offense.”

Dunn sailed the below lob pass out of the pick-and-roll too high for Cristiano Felicio. Maybe it was jitters. Maybe it was rust. Maybe it slipped. Maybe the two just don’t have great chemistry yet. But there’s no reason to think that timing won’t come. When it does, it’ll be a routine two points and add a wrinkle Grant doesn’t currently offer. Felder works well in the pick-and-roll. But he’s more of a scorer than a facilitator. Dunn has a chance to keep defenses off balance by offering the Bulls both.

After this play stagnated, Lopez got the ball to Dunn, and he made something out of nothing. Using Lopez’s ball screen, Dunn attacked the basket and forced the Thunder to help. When he drew two defenders — and a third set of eyes in Adams watching on the weak side — Dunn flicked a pass to a wide open Quincy Pondexter for a wing 3. Good execution. The shot just didn’t drop.

This play best highlights the difference between Grant’s steady distributing and Dunn’s potentially stellar playmaking. Dunn created this corner 3 for Holiday. After going away from Lopez’s screen, Dunn got Jerami Grant on his hip and “put him in jail” on his backside at the foul line. But rather than settle at the second level of the defense, Dunn kept attacking. He got to the next level at the rim, where he drew three defenders before firing the pass from beneath the basket to a wide open Holiday, whom Paul George left to help on Dunn’s drive. Plays like this are ideal for Hoiberg’s system. When Dunn attacks like this, he will get defenses swarming in pursuit of the ball and free shooters. Dunn is quite possibly the only player on the active roster who can consistently command this level of attention and create clean shot opportunities for others.

Attacking the rim

It remains to be seen what type of scorer Dunn will be at this level. But we know he’ll be able to get to the basket. “He gives us a downhill threat,” Hoiberg said. Dunn showed as much in his debut Saturday, unleashing several ferocious gallops to the rack.

Here we see Dunn’s best drive from his debut. Using a Felicio high ball screen, Dunn easily gets past Felton before putting Patrick Patterson in a blender with a beautiful spin move. Dunn then finishes the play with a gorgeous left-handed finish. Grant might be able to put this level of pressure on a defense on occasion, but while adjusting to his facilitator role he hasn’t consistently shown that level of assertiveness. Holiday appears happy to hoist shots from downtown. Valentine may dazzle every now and then. But Dunn offers this dynamic nightly. It will be invaluable when plays break down and the Bulls need someone to get a bucket.

Two final examples of hard drives by Dunn. On both, he barrels to the basket but meets quality defense at the rim, as the Thunder defenders go straight up both times and force Dunn into misses. Time will tell whether Dunn will be able to finish such plays with regularity. But you can see he has a knack for getting to the cup. That alone boosts Dunn’s value given the roster’s deficiencies in that department.

Remember, too, how much the Bulls struggle to generate free throws. They currently rank 26th at just 18 free throw attempts per game. Dunn’s assertiveness undoubtedly will help in that category as calls start to go his way. Of course, if he’s named the starter this week, Dunn will have to find a way to maximize his strengths while minimizing his weaknesses against superior competition. Whether he’s up for the challenge will first be determined by Hoiberg and his staff on the practice court. It’s a big Monday for the Bulls. It’s even bigger for Dunn.

(Top photo: Jerome Miron/USA TODAY Sports)