SAN FRANCISCO - Yahoo Inc.'s steadily sinking stock pulled out of its descent Tuesday on reports that the Internet pioneer is reconsidering its recent decision to fall into the arms of online search leader Google Inc. instead of Microsoft Corp.

The prospect of Yahoo spurning Google in favour of an alternative deal with Microsoft cheered investors still disillusioned with Yahoo's rejection of a US$47.5-billion takeover offer from Microsoft.

Yahoo shares climbed 59 cents, or 2.8 per cent, to finish Tuesday at $22.04 -- the stock's largest one-day gain in two weeks. The shares have been shrivelling since Yahoo announced it will use Google's technology to show some ads on its website in the United States.

When it embraced Google, Yahoo terminated talks with Microsoft about a sale of the entire company as well as a more limited deal focused on Yahoo's search engine. That led to a 16 per cent drop in Yahoo's market value, making it even harder for Yahoo board's to justify its decision to turn down Microsoft's last takeover offer of $33 per share. Yahoo CEO Jerry Yang had sought $37 per share.

Yang is now under intense pressure to prove Yahoo is worth as much as he thinks while also trying to fend off a shareholder revolt being led by activist investor Carl Icahn.

To make matters worse, Yahoo is facing a leadership vacuum created by the departures of several top executives and engineers. The company is expected to address the exodus in a reorganization to be announced this week.

The backlash to the Google alliance may have prodded Yahoo to rekindle talks to sell its search operations to Microsoft as part of a $9-billion deal.

Technology news site CNet.com and the blog Silicon Alley Insider both reported Yahoo and Microsoft are once again exploring a more limited deal, perhaps at a higher price than was previously discussed. The reports cited unnamed people familiar with the discussions.

Yahoo spokeswoman Tracy Schmaler declined to comment on those reports. Microsoft had no comment Tuesday, but the software maker has said it's still willing to consider a more limited deal with Yahoo.

The Silicon Valley blog TechCrunch raised Wall Street's hopes even higher by reporting Microsoft is mulling another offer to buy Yahoo in its entirety. TechCrunch's story also was based on information from an unnamed person.

But a source close to Yahoo told The Associated Press that there are no negotiations involving a complete takeover of Yahoo. The person isn't authorized to speak on behalf of Yahoo.

If nothing else, Wall Street's enthusiastic reaction to the reports Tuesday served as yet another reminder that Yahoo shareholders like the idea of the company teaming up with Microsoft instead of Google.

Yahoo needs to be even more responsive to shareholder concerns than usual because Yang and the rest of its board are facing a challenge at the company's Aug. 1 annual meeting.

Upset by Yahoo's handling of the Microsoft negotiations, Icahn has nominated an alternate slate of directors and promised to fire Yang as CEO if he wins control of the board.

Although the Google partnership is supposed to boost Yahoo's annual revenue by about $800 million, industry analysts think it might hurt Yahoo in the long run by ceding too much power to Google. Yahoo's growth decelerated in recent years primarily because it didn't keep pace with Google's innovations.

The Google partnership also faces the uncertainty of an antitrust review by government regulators and U.S. lawmakers. Together, Yahoo and Google control more than 80 per cent of the U.S. search advertising market.

Google and Yahoo have voluntarily delayed beginning their partnership until late September to address the competitive concerns.

If Yahoo strikes an alternative deal with Microsoft, Google will be owed a termination fee of up to $250 million.