SAN FRANCISCO (AP) — Yahoo Inc.’s first-quarter profit fell 11 percent, disappointing investors who have been betting that the internet icon had regained its stride after stumbling through much of last year.The letdown zapped Yahoo’s stock, which plummeted more than 8 percent after the results were released yesterday. Management added to the angst by leaving its financial outlook for the remainder of the year unchanged from its last forecast three months ago.

The Sunnyvale, California-based company earned $142.4 million (euro105.1 million), or 10 cents per share, during the three months ended in March. That compared with net income of $159.9 million, or 11 cents per share, for the same period last year.

The results were a penny below the average earnings estimate among analysts surveyed by Thomson Financial.

Revenue for the period rose 7 percent to $1.67 billion.

After subtracting advertising commissions, Yahoo’s revenue totalled $1.18 billion. That figure fell about $25 million shy of the average analyst projection, according to Thomson Financial. “When you sift through everything, there is not a whole lot to get excited about right now,” said Cantor Fitzgerald analyst Derek Brown.

Yahoo shares shed $2.61, or 8.1 percent, in extended trading after gaining 48 cents to close at $32.09 on the Nasdaq Stock Market.

The first-quarter downturn may renew concerns about Yahoo’s ability to compete against Google Inc., whose internet-leading search engine propels the web’s most lucrative advertising network.

Through March, Google held a 48 percent share of the US search market compared with 27.5 percent for Yahoo, according to comScore Media Metrix.

The balance of power will likely come into even sharper focus on Thursday when Mountain View, California-based Google is scheduled to report its first-quarter results.

Yahoo has pledged to narrow the gap with its rival this year with the recent introduction of a new marketing platform — dubbed “Panama” — that is supposed to do a better job of distributing ads that will spur revenue-generating clicks. Meanwhile, Google is bolstering its arsenal with its planned $3.1 billion acquisition of a major online advertising placement service, DoubleClick Inc.