Augustin forced overtime by hitting three free throws with 19 seconds left after Rose fouled him on a 3-point attempt. Augustin put it away with four more from the line in the final 42 seconds of OT, giving Charlotte an unlikely win as it played most of the game without two starters.
Rose had a rare bad game in what's been a remarkable rookie season for the No. 1 overall pick, held to six points on 3-of-16 shooting, with seven assists.
Rose had a potential game-winning shot blocked by Emeka Okafor at the end of regulation and Okafor blocked him again just before Augustin's free throws put Charlotte ahead 105-100.
Ben Gordon scored 25 points and Tyrus Thomas added 22 for the Bulls, who dropped to 3-10 on the road and failed to reach.500 for the first time in a month. Luol Deng had 15 points, but missed a key stretch at the end of regulation and OT after limping off the court clutching his hamstring. He returned late, but then fouled out.
Okafor added 20 points, 13 rebounds and four blocks, and Raymond Felton scored 21 points as the Bobcats persevered with a small lineup.
The Bobcats played for the fourth time in six games without leading scorer Gerald Wallace, whose father and grandmother have died this month. Wallace is expected to rejoin the team Friday at Memphis after attending his father's funeral.
That left 35-year-old Juwan Howard, signed last week, as Charlotte's starting small forward as coach Larry Brown tries to find the right combination after last week's trade that sent Jason Richardson to Phoenix.
Then one of the new players from that trade, starting shooting guard Raja Bell, was ejected late in the first quarter for abusive comments directed at referee Eli Roe. Bell had missed his first five shots and was talking with Roe during a break before a free throw attempt when Roe came over to the scorer's table and emphatically whipped his arm to signal the ejection.
So Charlotte went small, with point guards Felton and Augustin playing together. They spearheaded a 20-6 third-quarter run that put Charlotte up 65-59 on Matt Carroll's 3-pointer.
There were six ties in the fourth quarter, the last coming thanks to Rose's mental error.
Rose, in a one-on-one matchup, fouled Augustin from the left wing. Augustin, the ninth pick in the draft and a 93 percent free-throw shooter, calmly sank all three shots to tie the game.
Rose never gave up the ball on the next possession, driving past Augustin to the hoop, but his runner in the lane was swatted away by Okafor to force overtime.
Augustin hit all 13 free throws, had seven assists and just one turnover.
Notes: Bernie Bickerstaff was back for the first time since leaving the Bobcats after last season. Bickerstaff, now a Bulls assistant, was the expansion Bobcats' first coach and GM, but lost his decision-making power when Michael Jordan became part-owner. Bickerstaff, who chatted with Bobcats players and team employees before the game, said he's happy to be coaching again.... It was a homecoming for Bulls coach Vinny Del Negro, too. He played at North Carolina State and his wife is from Charlotte.... Bobcats F Sean May (knee, conditioning) was inactive again, and slumping F Adam Morrison didn't play despite being healthy.