NEW YORK — Shares of Marathon Oil Corp. could be under pressure Wednesday with crude prices on the decline and also a downgrade from Credit Suisse following disappointing earnings.

Before the market opened, shares fell about 2 percent in electronic trading.

Marathon shares fell almost 5 percent Tuesday, closing at $29.12, after reporting net income that rose almost 41 percent. The quarter included the spinoff of Marathon Petroleum Corp., but adjusted earnings rose 56.6 percent.

Unplanned downtime at some of its international operations hurt sales, although it said that those operations are already back to capacity.

Credit Suisse( CS – news – people ) analyst Edward Westlake downgraded Marathon to “Neutral” from “Outperform” Wednesday and said the stock could “pause for breath” because of earnings cuts and uncertainties about the larger market for oil. He also said many investors are waiting for Marathon to “demonstrate execution in the onshore liquids to prove its critics wrong.”

Excluding special items, Marathon’s adjusted income amounted to $2.29 per share. Analysts, who typically exclude special items, expected earnings of $1.93 per share, according to FactSet.

Westlake cut his earnings expectations by 1 percent this year and 13 percent in 2012, and lowered his price target to $36, down from $42.

Its shares are “slightly undervalued” on longer-term 2013 measures once onshore drilling growth happens, Westlake wrote. “However, the shares could tread water until the onshore execution track record is proven,” he wrote.

Shares fell 62 cents to $28.50 in premarket trading.