In light of the major declines in oil prices on Monday, Dennis Gartman, who shockingly turned bullish on the commodity last week, admitted that the call was a mistake and said he was shifting his position.
"Clearly, I was not expecting to see 500 points on the Dow or 1,000 points off the opening, Gartman said in an interview on CNBC's "Fast Money," noting that oil prices had also fallen sharply overnight.
"I had no choice but to say I'm wrong on being early… It was a clear mistake, a bad timing decision on my part. You have to go to the sidelines."
On Friday—just two days after the author of "The Gartman Letter" would continue to the point of a "panic liquidation"—Gartman announced that he had turned bullish on oil, citing structural shifts in the crude market.
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In a Friday note, he wrote, "For having been overtly and rather relentlessly ... and very publicly ... bearish, we are this morning turning bullish of crude oil, and we are turning so because the term structure shifts mandate that we do so."
"We do not make this statement lightly for this is a material shift in our view of the energy market ... a very material shift," said Gartman, who is sometimes referred to as the "commodities king."
The call took some by surprise since Gartman warned in March that oil could hit $15 a barrel by the year's end.
U.S. light crude closed down $2.21, or 5.5 percent, at $38.24 a barrel, which was the lowest since February 2009. Steep losses last week capped the contract's longest weekly losing streak since 1986.
was trading down $2.70, or about 6 percent, at $42.80 a barrel, after hitting a session low of $42.51, its weakest since March 11, 2009.