Bank of America analyst Doug Leggate had a change of heart concerning Chevron CVX, giving the oil company a double upgrade to buy from sell.
The analyst also lifted his ratings on a number of other oil producers. Energy companies were mixed in volatile Monday trading.
Leggate said that his initial reaction to the recent slump in oil prices and the economic outlook generally was to downgrade the energy sector pending more clarity.
But Leggate said his stress tests led him to believe that some of the names he downgraded moved too sharply down.
The double upgrade wasn't enough to stop Chevron's slide Monday as the stock dipped double digits during the afternoon session as oil prices continued to fall amid a pricing war between some of the world's largest crude producers.
At last check, Chevron shares were down 7% to $55.24.
EOG Resources edged down 0.3% to $34.80 while Devon Energy advanced 1.8% to $6.19. Noble Energy shares jumped 5.1% to $5.24.
Oil prices were also facing tough pressure on Monday .
International benchmark Brent crude was down 5% to $25.64 a barrel while West Texas Intermediate crude declined 2.25% to $22.21.
Oil prices slumped after Saudi Arabia and Russia failed to reach a production agreement and the kingdom ramped up output, launching a price war.