The Sensex opened with a huge negative gap of 103 points at 13,769, mainly on account of a sharp (14.5%) drop in Bharti Airtel at the opening bell. The index touched a low of 13,763, and soon rebounded into the positive zone as Bharti Airtel recovered from its opening freak trade. The index rallied to a high of 13,972, before slipping back into the negative zone in late noon deals.The index heavyweights exhibited mixed trend today. While HDFC, ONGC and ICICI Bank rallied, Reliance Communications, Maruti and ITC dropped.The Sensex finally settled with a marginal loss of 11 points at 13,861. The index, however, ended higher for the second straight week, up 74 points.