The flu is one of the many potholes that temporarily can derail a college basketball team during the long and challenging winter schedule. It has been around forever, so trainers and doctors know how to treat it. Coaches know how to deal with its consequences.

The new, rare bug that has engulfed the star-studded KU roster is another matter. College basketball coaches don’t have much experience dealing with it, particularly at the superpower level.

The bug is called C.S.

Symptoms: Young athletes listen to the voices that critique their games honestly. They ignore the ones that tell them how great they are because they want a permanent front-row seat to big-time fame and fortune if it arrives.

Brandon Rush exhibited a serious case of C.S., aka common sense, in deciding not to declare himself eligible for the 2006 NBA Draft. Such a move would have set him back academically and would have led to the scouts telling him what they told him a year ago, when he participated in the NBA Draft camp. They told him he wasn’t ready and told him what to work on. Rush listened. He improved his outside shot and his defense, both of which he’ll continue to refine. This time, they would have told him to work on his left hand, nothing he didn’t already know.

Rush’s decision to return says a lot about him. It says he doesn’t have an inflated opinion of himself, and it says how thoroughly he’s enjoying the latter half of his student-athlete responsibilities. Rush makes no secret of his distaste for academic pressures, so it’s not as if he took the easy path here. Very often, the easy path isn’t the wise one. Rush had enough maturity to choose the sensible path.

Rush turns 21 on July 7. If he makes the anticipated improvements to his game during his sophomore season and then bolts to the NBA, he’ll be a 22-year-old rookie.

Julian Wright turns 19 on May 20. If he books after his sophomore season, he’ll be a 20-year-old rookie.

A freakishly explosive leaper with a terrific attitude, Wright could have taken a test run, too, and decided to take the wise path. He’s not close to the player he’ll become. He made big strides as a freshman, but hasn’t put it all together yet.

“He will,” a veteran NBA scout said. “Trust me. He will. And when he does, look out.”

Because Wright didn’t test the NBA waters this year, he can do so a year from now and could be told he’s ready then.

Daniel Gibson and P.J. Tucker of Texas are taking test runs and can return to the Longhorns because they haven’t hired agents.

“Gibson didn’t help himself at all this year,” another NBA scout said. “He needs to come back.”

The same scout on Tucker: “Come on. Picture him playing against the Spurs. You think Mr. Duncan might have something to say about the stuff he throws up inside?”

Evidently, Akbar Abdul-Ahad, a 6-foot junior from Idaho State, found the cure for C.S.: a healthy dose of foolishness. Abdul-Ahad averaged less than six points in 20 minutes per game. He scored three points and made one of six shots in an Allen Fieldhouse loss to the Jayhawks.

Abdul-Ahad hasn’t hired an agent, though it’s not clear whether he wants to keep his options open or nobody was interested in representing him.