By Cody Westerlund–

(CBS) The Tom Thibodeau era in Chicago has come to an end.

After five years coaching the Bulls, Thibodeau has been fired, the team announced Thursday morning. The news comes as no surprise after the well-documented clash of philosophy between the hard-driving Thibodeau and Bulls management in recent years grew from a small issue to an untenable professional relationship.

Thibodeau, 57, had two years and about $9 million left on his contract. Iowa State coach and former Bull Fred Hoiberg is widely believed to be the front-runner to replace Thibodeau.

“The Chicago Bulls have a history of achieving great success on and off the court,” chairman Jerry Reinsdorf said in a statement. “These accomplishments have been possible because of an organizational culture where input from all parts of the organization has been welcomed and valued, there has been a willingness to participate in a free flow of information, and there have been clear and consistent goals.

“While the head of each department of the organization must be free to make final decisions regarding his department, there must be free and open interdepartmental discussion and consideration of everyone’s ideas and opinions. These internal discussions must not be considered an invasion of turf and must remain private. Teams that consistently perform at the highest levels are able to come together and be unified across the organization — staff, players, coaches, management and ownership. When everyone is on the same page, trust develops, and teams can grow and succeed together. Unfortunately, there has been a departure from this culture.

“To ensure that the Chicago Bulls can continue to grow and succeed, we have decided that a change in the head coaching position is required. Days like today are difficult but necessary for us to achieve our goals and fulfill our commitments to our fans. I appreciate the contributions that Tom Thibodeau made to the Bulls organization. I have always respected his love of the game and wish him well in the future.”

Thibodeau departs as the second-winningest coach in Bulls history. He went 255-139 in his five-year tenure, a winning percentage of .647. Phil Jackson is the franchise’s all-time coaching wins leader, as he had a mark of 545-193 (.738) from 1990-’98. Thibodeau also led Chicago to a playoff appearance in each of the past five years.

“When Tom was hired in 2010, he was right for our team and system at that time, and over the last five years we have had some success with Tom as our head coach,” Bulls general manager Gar Forman said in a statement. “But as we looked ahead and evaluated how we as a team and an organization could continue to grow and improve, we believed a change in approach was needed.”

Thibodeau burst onto the scene after being hired in June 2010 following a successful stint as a Celtics assistant and defensive coordinator. He led the Bulls to a league-best 62-20 mark in his first season and was named Coach of the Year before the Bulls fell to the LeBron James-led Heat in five games in the Eastern Conference Finals.

The success of the Thibodeau-led Bulls was made all the more remarkable by the devastating injuries that star Derrick Rose has suffered in recent years. Since April 2012, Rose has had two major knee injuries and three surgeries, and he played in just 100 of Chicago’s 312 regular-season games in the past four years.

Through all the obstacles, Thibodeau led the Bulls to a 50-16 mark in 2011-’12, a 45-37 mark in 2012-’13, a 48-34 mark in 2013-’14 and a 50-32 mark this past season. In games in which Rose played in Thibodeau’s tenure, including the playoffs, the Bulls posted a winning percentage of .704.

The origins of tension between the front office and Thibodeau aren’t clear, but Forman’s decision to not renew loyal Thibodeau assistant Ron Adams’ contract in June 2013 could’ve been a flash point for the relationship breaking down. It’s common practice for head coaches to make decisions on their staffs in the NBA, even if management has the final say, and the decision was widely viewed as a breach of trust.

More recently, the front office took exception to Thibodeau’s intense style, and the relationship continued to deteriorate. A Bulls player (either Luol Deng or Jimmy Butler) has led the NBA in minutes each of the past four seasons, and some believed Thibodeau’s ways contributed to Chicago’s injury problems and/or tendency to look worn down in being eliminated from the playoffs each season.

Bulls management went so far in 2014-’15 as to institute minutes limits for Rose, Joakim Noah and Kirk Hinrich. There were also practice limitations for some players, according to reports. A by-product of Thibodeau’s reliance on his go-to players was the delayed development of some young players, such as rookie Doug McDermott this past season. The Bulls traded two first-round picks to acquire McDermott with the 11th pick last June, but he rarely factored into the regular rotation.

Restrictions of any sort never sat well with Thibodeau, who while not directly criticizing them constantly stressed that the ultimate goal could only be reached by creating continuity with the best effort in games and practices.

“The magic is in the work,” Thibodeau said on multiple occasions.

The Bulls front office also had concerns about Thibodeau’s offensive philosophy, encouraging him at one point to hire a more offensive-minded assistant. That didn’t happen.

Comments from ESPN analyst Jeff Van Gundy — a friend of Thibodeau’s — during a January TV broadcast also added to the tension between Thibodeau and Bulls management. Van Gundy accused Bulls management of historically undermining their coaches, which incensed Paxson, Forman and reportedly Reinsdorf as well. Many saw Van Gundy serving as Thibodeau’s mouthpiece, whether it was true or not.

Any faint hopes of a professional reconciliation between Thibodeau and management vanquished when the Bulls were eliminated in an embarrassing 94-73 loss to the Cavaliers in Game 6 of the Eastern Conference semifinals on May 14. While the 50-win regular season was a success, these Bulls were being judged by the championship aspirations they set for themselves.

“I’m proud of our guys,” Thibodeau said after the season-ending loss. “We came up short.”

It marked the third time in five seasons that Chicago’s season ended at the hands of a James-led team.

Throughout this tumultuous past season in which Thibodeau often found speculation regarding his future in the headlines, he never expressed any second thoughts about his approach.

Thibodeau knew only one coaching style — as intense as possible all the time — and he stuck with it. It was was the catalyst for his success and, in the eyes of some, his failures.

“I’ve been around a long time, so I understand when you go through things, it’s all part of this,” Thibodeau said on March 18 after a win. “So for me, it’s you block out all the noise and concentrate on our job, just go out and do your job to the best of your ability. I have no regrets. I’ve put in everything I have into each and every day. I’m going to let the results (speak). I’m good with that.”

Cody Westerlund is a sports editor for CBSChicago.com and covers the Bulls. Follow him on Twitter @CodyWesterlund.