UPDATE 2-Acergy 2010 forecast down, shares hit

* Operating profit down at $77 mln vs $54 mln from analyst

* Sees lower 2010 revenues, margins

* Strong cash position, will consider acquisitions

* Shares down 0.4 pct after pre-statement high of 3 percent

(Adds details, company and analyst comments; updates shares)

OSLO, Oct 14 (Reuters) - Oil and gas contractor Acergy S.A. (ACY.OL) on Wednesday forecast revenues and margins to drop in 2010 after it reported a forecast-beating third-quarter operating profit, sending shares down.

Shares of the company -- up around 3 percent ahead of the earnings release -- were down 0.4 percent to 74.75 crowns by 1502 GMT against a 2.2 percent rise on Oslo bourse' benchmark index .OSEBX.

Acergy, which supplies engineering and construction services to the oil and gas industry, said its business environment remained challenging.

"While we remain cautious in the short term, the medium term outlook remains strong," Chief Executive Jean Cahuzac told a telephone conference.

Acergy said the medium-term would be driven by increasing field depletion and a need for oil firms to access new reserves.

"These were good figures, but a somewhat soft 2010 guidance," First Securities analyst Paal Dahl said. "The share rose ahead of results so this (price fall) may be some profit taking given that the guidance is somewhat soft."

2010 REVENUES, MARGINS DOWN

Acergy said it continued to build backlog for execution in 2010 and beyond, but that it expected 2010 to see lower revenues and margins due to keener competition for recent and new tenders resulting in price pressures.

Analysts in a Reuters poll forecast revenue of $2.10 billion for 2009 and $2.09 billion in 2010.

Third-quarter operating profit came in at $77 million compared with an average forecast for $54 million in the Reuters poll and down from $153 million in the year-ago period.

"Based on our current view, we expect revenue from continuing operations for fiscal year 2009 to be in line with previous guidance," Acergy said in a statement.

Acergy said in April that it expected revenues to decrease this year to levels marginally lower than the consensus, which had been $2.2 billion in a Reuters poll.

"Subject to the successful outcome of a number of commercial negotiations in the final quarter of fiscal year 2009, we expect to achieve an adjusted EBITDA margin from continuing operations, above previous guidance, although below the outturn for fiscal year 2008," Acergy said.

Third-quarter revenue fell 13 percent to $558 million against analysts' expectations of $550 million.

Acergy said its balance sheet was strong and that the current market situation might present possibilities.

"We have a strong cash position which will enable us to manage through the cycle. We are very well positioned to look at asset opportunities as they emerge," Acergy said.

Vessel utilisation stood around 83 percent in the third quarter, but was expected to be lower in the fourth quarter.

(Reporting by Richard Solem, Joergen Frich and Aasa Christine Stoltz; editing by Simon Jessop and Karen Foster)