With Derrick Rose out for the season and Luol Deng in Cleveland, the Bulls have been short-handed all year.

Their formula for success against such odds has been simple: Defend. Rebound. Get to loose balls. Hit first and ask questions later. Be the aggressor.

Even after improving to 15-1 after their last 16 losses and pulling into a third-place tie with the Raptors in the Eastern Conference following a 91-81 victory over the 76ers, something is missing.

The Bulls were outrebounded for the fourth time in six games. They were beaten to loose balls. They finished on the short end of a 22-9 tally in second-chance points.

In short, with both teams finishing the second of back-to-back games, the 76ers played like the hungrier team, not one headed to their 24th straight defeat.

"We have to change it," coach Tom Thibodeau said. "To do the things we want to do, we have to be great defensively and with our rebounding."

The Bulls did limit the 76ers to 34.5 percent shooting and a 0-for-18 start from 3-point range, which fell just four misses shy of tying the Nuggets' NBA record.

And the 76ers are bearing down on another mark of futility. They now posses the second-longest, single-season losing streak in NBA history, just two games shy of tying the Cavaliers' record from the 2010-11 campaign.

But whether this is a temporary blip of the cumulative effect of playing short-handed all season, the Bulls' edge isn't currently as sharp as usual.

"It's a concern," Joakim Noah said. "We have to come back with a better effort.

"Every team is going through the same thing. The teams that are mentally strongest, those are the teams that usually win. The teams with an edge, the teams that come with competitive spirit and want it more, I wonder what the percentage of those teams winning is? I'm sure it's favorable."

Noah's 20 points led four Bulls in double figures, though his streak of leading the team in assists ended at nine games. Jimmy Butler added 17 points, eight rebounds and six assists in another yeoman effort.

Scoring has been an issue all season, obviously, with the Bulls stuck in last place at 93.2 points per game. This is the time of the year when teams are pretty much what they are. And the Bulls' offense is such that their margin of error for victory remains slim.