Oil prices slipped below the psychologically important level of $40 a barrel during trading Monday, and another $5 drop could be on the horizon, according to analysts.
Bets that U.S. crude's West Texas Intermediate contract will rise have "pretty much evaporated" as the assumptions underpinning the bull case for oil have collapsed, Again Capital founding partner John Kilduff told CNBC.
A Reuters survey released Friday showed OPEC output likely hit the highest level in recent history. On the same day, oilfield services firm Baker Hughes reported drillers increased the number of rigs operating in U.S. fields for a fifth straight week.
Meanwhile, Saudi Aramco reduced the official selling price of benchmark Arab light grade, sparking fears of a renewed battle for market share among OPEC members that could put more crude into an already oversupplied market.
Oil watchers had already feared another leg lower as refined-products stockpiles hit record levels, reducing demand for crude just as peak driving season in the United States comes to a close and refiners prepare to shut facilities for fall maintenance.
"There was a thought the strong gasoline demand would drain the swamp but it hasn't," Kilduff said, adding that "I think we're going to ultimately head down to at least $35."