Blake hasn't won a doubles title since 2004, while Fish has won two this year with different partners.
"To be honest, we feel like we can win any tournament," Fish said after they defeated Simon Aspelin of Sweden and Paul Hanley of Australia 7-6 (5), 6-4, 7-6 (5) Wednesday in the quarterfinals. "We've won tournaments before, but it has been a little while. And we've beaten almost everybody out there. If we're both playing well we can do really well."
For a while, though, it looked like they may not even be able to enter the doubles tournament. Blake lost to Andreas Seppi of Italy in the first round in singles, and Fish told him it was OK if he wanted to skip doubles.
However, Blake decided to stick around since he is playing in the Davis Cup quarterfinals in Croatia later this month.
"It makes a difference playing with a good friend and someone who is fun to play with," Blake said. "He sent a text right away that he'd understand if I needed to go, needed to leave, which was great. That's another good thing about playing with a singles player, who knows that (losing) feeling."
Fish lost in the third round to Novak Djokovic.
Blake and Fish upset third-seeded Lukas Dlouhy of the Czech Republic and Leander Paes of India in straight sets in the first round. They will next face second-seeded Daniel Nestor of Canada and Nenad Zimonjic of Serbia.
Neither Blake nor Fish had ever made the quarterfinals at Wimbledon before, in singles or doubles.
"Now we're in the Final Eight Club," Fish said.