Chicago ? Now that the Bulls put all that silliness behind them and made Ben Wallace take off the headband, it’s time they faced up to the real problem.

That would be the one between his ears.

We already know what Wallace can do when he’s happy. He proved that again Tuesday night against New York, providing a little grit and a lot of energy as the Bulls completed a home-and-home sweep of the fast-fading Knicks. What remains to be seen is whether he and coach Scott Skiles can be happy at the same time.

For the first three weeks of a contract that will pay him $60 million over the next four years, Wallace played – and maybe worse, behaved – like a homesick freshman instead of the reigning NBA defensive player of the year. He looked lost, on the court and off. He called pals back in Detroit all the time and sulked. His stat lines from Chicago’s first dozen games – 9.2 rebounds, 5.5 points and 1.5 blocks per game – suggested Wallace might be phoning those in, too.

We don’t have to imagine how that went over with Skiles, whose old-school playing pedigree traces back through the NBA and Michigan State, all the way back to his days as an Indiana prep sharpshooting legend. And he is no less old-school as a coach. Asked three years ago what a promising youngster named Eddy Curry could do to improve his rebounding, Skiles didn’t hesitate.

“Jump,” he replied.

Only Wallace knows why he decided to test those credentials last Saturday night in New York, at the tail end of a five-game losing streak, no less. Maybe it was the 0-for-Philly in the previous night’s game, or because Skiles cut off his playing time at 19 minutes. By that point, Wallace and the coach had reportedly tangled over practice and music, so maybe it was something else.

Either way, Wallace started the Knicks game by defying team rules and donned a red headband. As far as Skiles was concerned, he might as well have been waving a cape. Once he saw it, the coach yanked Wallace from the game, then did it again when his center put the headband back on to start the third quarter. As for the two of them butting heads afterward, suffice it to say that few teams hold a 25-minute closed-door meeting following a win.

“Headband-gate” had two more days to run, and if there was a dumber argument in sports at that moment, it went unnoticed. Near the end of all that wasted time and effort, Skiles thought he detected a silver lining in the parting clouds.

“I don’t think it’s the worst thing in the world for them to see some confrontation like that,” he said about his team, “as long as it gets resolved.”

If Skiles is lucky, he might look back on Tuesday night as the moment the resolution started. More specifically, he might look back at a 6-second sequence when Wallace drove to the basket and missed a layup, fought for the rebound, missed another layup, fought for that rebound, then drove underneath the basket and finally put a reverse layup in.

“There are other guys who go out there with energy and really don’t do anything. When he has energy,” Skiles said about Wallace, “he plays very well.”

That translated into nearly all the Bulls playing well, then pulling away to win handily 102-85 – a result to which Wallace contributed eight points, 12 rebounds, two blocks and two assists in 38 tough minutes. But you wouldn’t have guessed that had you seen Wallace and his coach at a shootaround earlier in the day.

At the practice, Wallace acknowledged he knew he was breaking the rules by wearing the headband, that he had no regrets doing it, and that he’d happily suffer whatever punishment and/or fine the club decides on. And you would have heard Skiles carrying on about how – in addition to paying hefty salaries – the team provides chefs to cook the players lunch, flies them everywhere first-class and pays porters to carry their luggage on the road.

“So much is done for the players, we ask for so little back,” he began, then caught himself.

“I’m not one of those ‘when-I-played’ guys,” he added. “I was the beneficiary of all those things.”

And like Skiles, Wallace has always been an team-first guy. But to Skiles’ way of looking at things now, the guy that’s supposed to be leading his team star is a 32-year-old mercenary who’s making roughly $3 million more a season in Chicago than he would have in Detroit. And the last thing the coach wants to discover is that Wallace’s best efforts, not to mention his best years, are already behind him.

For one night at least, the Bulls got their money’s worth. Winning makes everybody happy – it always does – but beating the Knicks isn’t why the organization lavished a big contract on Wallace. Skiles is going to demand that same effort every night from here on out, and if there’s going to be more head games ahead of the actual ones, Wallace would do himself well to get them out of the way sooner rather than later.