During a season highlighted by a runner-up showing in Dubai and semifinal runs at Sydney and the Australian Open, the Americans came into Miami fifth on the Road To Singapore leaderboard. They avoided falling in the first round here for the fourth straight year by winning a match tie-break against Kristina Mladenovic and Flavia Pennetta on Friday - their 125th WTA victory as a duo.
Kops-Jones and Spears' second round tilt on Sunday against Vania King and Zheng Jie also came down to a match tie-break, where from 6-5 down they reeled off five straight points to clinch a 36 75 106 triumph that actually saw them lose 12 more points than they won.
"It was a very difficult match," Kops-Jones said. "We played really great players today. We tried to be consistent and really played a good super tie-break."
Next up for Kops-Jones and Spears are Spaniards Garbiñe Muguruza and Carla Suárez Navarro, who a day after stunning third-seeded Sara Errani and Roberta Vinci, were 62 60 winners over Janette Husarova and Iveta Melzer in 51 minutes.
Also advancing to the quarterfinals were Alla Kudryavtseva and Anastasia Rodionova, who rallied from a 4-0 second set deficit en route to a 63 75 defeat of Monica Niculescu and Klara Zakopalova in a match-up featuring duos who have each won two WTA titles this year. Kudryavtseva and Rodionova were victorious in Brisbane and Dubai and Niculescu and Zakopalova in Shenzhen and Hobart.