At 12.30pm, the index was down 13.37 points to 1,524.17, erasing most of the gains it had made in the previous session.
Trading volume was on pace with 5.09 billion shares valued at RM2.96bil.
After jumping 16 points higher in the previous session, hopes were raised that the index was embarking on a recovery trend.
According to Malacca Securities Research's technical outlook, the key index formed a bullish harami candle, which suggested a potential recovery patten from the recent pullback.
The research house set an immediate resistance of 1,540 for further recovery to take place.
However, a promising start in the early morning session soon gave way to profit-taking.
A sharp retreat was seen in Hartalega
, which lost 86 sen to RM14.50. Rival glove stock Top Glove was one of the few heavyweights to advance, following a two-for-one bonus issue.Following the dilution, the share rose 13 sen to RM8.82.
Other notable decliners included Tenaga Nasional falling 22 sen to RM11.02, IHH sliding eight sen to RM5.27, MISC dropping 12 sen to RM7.60 and Maxis dropping eight sen to RM5.02.
Top actively traded stocks were PHB down 0.5 sen to 3.5 sen, Pasukhas
sliding one sen to 12 sen and MQTech falling 0.5 sen to 20.5 sen.Meanwhile, oil markets saw some mild retracement after falling more than 2% overnight to multi-week lows as US data showed shrinking US gasoline demand.
US crude rose nine cents to US$41.60 a barrel while Brent crude gained three cents to US$44.46 a barrel.