Chicago Bulls' Derrick Rose (C) shoots on the San Antonio Spurs' Antonio McDyess (L) and Tim Duncan during the second quarter of their NBA basketball game in Chicago Feb 17, 2011. [Photo/Agencies]

CHICAGO- Derrick Rose scored a career-high 42 points to pace the improving Chicago Bulls to a comfortable 109-99 win over the NBA leading San Antonio Spurs on Thursday.

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The Bulls, well clear in the East Conference Central Division, picked up a fourth straight victory heading into the All-Star break, while the Spurs concluded their nine-game road trip to facilitate a rodeo in their home arena with six wins.

After briefly falling behind in the second quarter, Rose's 10 points helped the Bulls close the first half with a 15-7 run to carry a 58-51 advantage into the break.

The Spurs drew to within two points at 73-71 with 4:49 remaining in the third quarter but Luol Deng responded with a three-pointer and the Bulls cruised to victory.

Deng finished with 19 points and Carlos Boozer added 15 for the Bulls, while Tony Parker was the Spurs top scorere with 26 points.