PITTSBURGH—Red wine and candlelight on the table before them, Deep Blue, the supercomputer that defeated reigning world chess champion Garry Kasparov in 1997, and Kasparov’s ex-wife, Yulia Vovk, quietly celebrated their 10th anniversary on Wednesday at a small French restaurant near Carnegie Mellon University, where Deep Blue was created. Those close to the couple said the two first met during Deep Blue’s match against Kasparov in 1996, and though the Russian grandmaster beat the computer four games to two, Vovk and Deep Blue struck up a friendship and continued corresponding via email. Sources said the intimate but platonic relationship blossomed into an indelible romance after Kasparov and Vovk’s marriage fell apart in 2005—with Vovk often complaining to friends that the increasingly distant Kasparov was “more of a chess robot than Deep Blue.” Soon thereafter, the couple reportedly shared their first romantic dinner at the same restaurant where they celebrated the occasion a decade later, having married in 2007 and gotten past the brief dalliance Vovk had with Jeopardy! champion Watson in 2012.