It seems like trouble is brewing in the Chicago Bulls locker room as Most Improved Player Jimmy Butler comments on how bad Derrick Rose's work ethic has been last season.

According to Butler, Rose did not work hard enough despite being the face of the franchise and it gave a negative outlook for some of the players of the Chicago Bulls.

"According to the source, Butler considers Rose a friend, but 'doesn't have a lot of respect for his work ethic.'" Wrote  Joe Cowley of the Chicago Sun-Times. "In Butler's mind, Rose was considered the face of the franchise, and if the face of the franchise wasn't busting his butt in practice every day, especially last season, what was the message to the rest of the team?"

It is worth noting that it was Rose's more productive season as he was able to play as many games compared to the previous seasons which he spent mostly on the sideline since he is injured.

Now, Jimmy Butler is turning out as the main man in the Chicago Bulls line-up and earlier this off-season, both guys have had issues on who is this team's alpha dog.

"Sources describe a passive-aggressive reaction from Rose that was the culmination of tensions building in recent weeks with Butler's emergence as a primary scorer," wrote Dan Bernstein of CBSChicago.com. "Butler's emergence was validated by the NBA's Most Improved Player Award, and he's now feeling every bit the star, with all that entails."

Rose recently suffered an orbital fracture in his face that required him to undergo surgery once again. The good thing is it won't take months to recover from the surgery and he can return as early as the season opener.

Will Jimmy Butler's comments affect or improve the relationship between him and Derrick Rose? Stay tuned.