SAN FRANCISCO - Microsoft Corp. has finally roped Yahoo Inc. into an Internet search partnership, capping a convoluted pursuit that dragged on for years and finally setting the stage for the rivals to make an all-out assault against the dominance of Google Inc. 

The 10-year deal announced Wednesday gives Microsoft access to the Internet’s second-largest search engine audience, adding a potentially potent weapon to the software maker’s Internet arsenal as it tries to better confront Google, the leader in online search and advertising.