NEW YORK, Nov 14, 2007 (AFP) - John Thain, the next head of troubled investment bank Merrill Lynch, is a dean of US finance who forged the merger of the New York Stock Exchange and Euronext into the world's largest stock market operator.

Once the leader of Goldman Sachs, Thain, 52, will take the helm of that firm's troubled rival Merrill Lynch as chief executive and chairman on December 1, the company said Wednesday.

'It's a great opportunity for me. I'm excited about it,' Thain said in an interview on CBNC television that coincided with the Merrill Lynch announcement.

'I think I can make a difference there,' he said, adding, 'I think it will be fun.'

The NYSE Euronext CEO comes to the ailing investment bank after engineering last year's massive transatlantic merger between the two bourse operators, a strategic coup for the New York exchange at a time of global stockmarket consolidation.

He joined the venerable 214-year-old US market operator in January 2004 as chief executive and pushed its modernization, taking the NYSE itself public and introducing electronic trading alongside its traditional 'open cry' floor trading.

Before arriving at the New York exchange, Thain held a series of high-profile posts at Goldman Sachs before rising to become president of the investment banking titan in May 1999.

Thain arrived at NYSE to succeed Richard Grasso, the disgraced chief forced out after a scandal over his lavish pay.

Although Grasso raked in 140 million dollars a year at the NYSE, Thain accepted the CEO post for an annual income of four million dollars, one-fifth of what he had made at Goldman Sachs.

He is known for his eye for detail. He received an MBA from Harvard University in 1979 and a bachelor of science degree in electrical engineering from Massachusetts Institute of Technology in 1977.

At NYSE, he led the long merger process to create NYSE Euronext at the end of March, boasting a value of 25.81 billion dollars, making it the world's largest listed exchange group.

The leviathan combines markets in New York, Paris, Brussels, Amsterdam and Lisbon under one roof and also includes the Liffe financial futures market in London.

Asked Wednesday about international expansion plans for Merrill Lynch, Thain noted that his new employer 'has a global franchise.'

'There are always opportunities to expand.'