CBS Sports' Eye On Basketball continues to take a team-by-team look at the 2015 NBA offseason. Up next: the Chicago Bulls.

Tom Thibodeau, for all his faults, took the Bulls from a promising young team to a borderline contender. Immediately under his coaching, the Bulls became a 62-win team, one of the best defensive units in the NBA and a team that looked prime to challenge the Eastern Conference for years to come. Then the injuries hit. Their newly anointed star Derrick Rose suffered a knee injury that has stolen prime years from his career, and the Bulls were ultimately run into the ground by their coach's demands -- upsetting management in the process. This summer the Bulls decided to change their coaching situation, bringing in Fred Hoiberg in hopes that the shakeup will get them to the next level. How do things look in Chicago after the 2015 summer?

Key Additions

Fred Hoiberg (hired), Bobby Portis (drafted)

Key Losses

Tom Thibodeau (fired), Nazr Mohammed (unsigned)

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Did the Bulls get better this offseason? The roster, particularly the core of it, really hasn't changed at all, so in a way it's hard to say the Bulls got better. They decided to spend big money in retaining Jimmy Butler -- $87.8 million over five years -- locking him up as one of their big stars for the next half-decade, while also re-signing Mike Dunleavy (3 years, $14.5 million) and Aaron Brooks (1 year, $2.3 million). The only player who was a free agent for them who remains unsigned is Nazr Mohammed.

Chicago also used the 22nd pick in the draft on power forward Bobby Portis out of Arkansas. Portis is a relentless worker on the glass, a guy who will put everything he has into defending, and someone who can spread the floor a bit by hitting a jumper. He'll add to an already deep frontcourt of Joakim Noah, Pau Gasol, Taj Gibson and Nikola Mirotic.

But again, the roster is nearly identical to last year. We're still looking at a starting five of Rose, Butler, Dunleavy, Noah and Gasol. Maybe Doug McDermott takes a leap forward. Maybe Mirotic builds on his impressive rookie campaign. Maybe a healthy Noah returns to his Defensive Player of the Year form. But generally speaking, we pretty much know what we're going to get from this roster.

Except for Butler and Hoiberg. They're the wild cards. 

First, the former ...

Has Jimmy Butler become Chicago's best player, and if so, is that enough? Because of Rose's injury problems and Butler's notable rise to stardom, it's fair to wonder who the go-to guy is for the Bulls at this point. Rose had moments during this past postseason in which it looked like he was finally rounding back into form. He carried them for times against the Bucks. He had big stretches against the Cavs. At the same time, though, Butler was their most consistent player on both ends of the floor.

A healthy Butler for most of last season yielded a fantastic two-way player. He made the All-Defense Second Team and was certainly in the running for All-NBA Third Team. He was the player who carried the Bulls the most as they regained their 50-win form. In a perfect world, Rose would return to his MVP form and resume his role as the Bulls' go-to guy, but at this point, that seems nearly impossible. So Butler likely becomes that guy.

It's a quick ascension to best player on a potentially top-four East team, similar to the leap Paul George made in 2013-14 when he led Indiana to the top seed in the East and finished Top 10 in MVP voting. Still, even George had limitations that year in terms of his ability to lead his team to true elite status -- which is to say, past LeBron James. To think Butler is ready to lift the Bulls to the top of the East, and particularly past an even more potent James-led Cavaliers team that will return a healthy Kyrie Irving and Kevin Love, seems a bit ambitious. 

In reality, the Bulls need Rose to be the old Rose, or at least something halfway close to it.

And ultimately, they need Hoiberg to get more out of this roster than Thibodeau did. 

Which brings us to the question we're really asking ...

Under Hoiberg, can the Bulls actually become a true title contender? For years, the Bulls, and especially their management, believed they had the right pieces to challenge whichever team LeBron James was leading. Injuries largely derailed that quest, but even with a relatively healthy team this past postseason, LeBron's Cavs, even minus Love, were too much for Chicago.

Enter Hoiberg. 

Matt Moore did a good job here of laying out what, exactly, Hoiberg should bring to the table with his fast-paced, 3-point heavy system. While talent -- not necessarily coaching -- usually dictated the effectiveness of Thibodeau's somewhat underrated offenses (Chicago was fifth in 2011-12, 10th in 2014-15), Bulls brass clearly believes Hoiberg can push the team over the top, not only with better minute management, but with an offense that took Hoiberg's Iowa State program from 146th in the country (out of 351 schools) in offensive rating to 16th, 28th, and 28th, respectively, over the last three years.

Three years ago, with an offense that should translate very favorably to today's NBA, the Cyclones hit and attempted the most 3-point shots in college basketball. They remained a top-40 team in terms of long-distance makes the past two years, and equally impressive, they kept a low turnover rate despite playing at a fast pace. 

This past season, the Bulls were 10th in 3-point percentage, but only 15th in makes and 16th in attempts. They played the 21st-fastest pace in the league. That will change under Hoiberg, and they're hoping the return of a relatively healthy Derrick Rose, along with the emergence of Butler, will be the right combination to maximize this offensive attack.

If the Bulls can keep the defensive mentality Thibodeau instilled, and adapt to what Hoiberg wants to do offensively, they believe that's enough to put them in the elite parts of the East with Cleveland, Washington, Atlanta and Miami. 

The big problem with this ideology is it assumes the Bulls will remain healthy, which has been nearly impossible for them to do over the past four years. If you believe Thibodeau and his unrelenting minutes demands was the cause of this team-wide breakdown, then you have to wonder if the damage has already been done. If not, perhaps Hoiberg's amenable rotations will curb the injuries. Either way, health will remain a major question mark as it pertains to Chicago's chances of ascending to championship contention. 

Incidentally, one of many questions. 

Is Fred Hoiberg the change the Bulls need? (USATSI)
Is Fred Hoiberg the change the Bulls need? (USATSI)