NEW YORK (AP) — Merrill Lynch & Co. has tapped New York Stock Exchange head John Thain to lead the world's largest brokerage through the unfolding credit market turmoil that threatens Wall Street's biggest investment houses, according to published reports Wednesday.

The Wall Street Journal and the New York Post are reporting that Thain, 52, has been selected to become Merrill's chairman and chief executive. There were reports that NYSE's board met during the day, and that an announcement could come later this afternoon.

Spokesmen for the NYSE and for Merrill declined to comment.

Thain, who is credited with remaking the NYSE into the world's first truly global exchange, is no stranger to the investment world. He started out on the bond desk at Goldman Sachs Group Inc. and left the firm as its chief operating officer.

Many say he's also exactly what Merrill Lynch needs after last month's ouster of Stan O'Neal. The former CEO was not well liked by Merrill's nearly 16,000 brokers, and lost their confidence after the company posted its biggest loss since being founded 93 years ago.