Roger Federer began his campaign at the WTA and ATP Miami Masters with a 6-4, 7-6 (7/4) defeat of Ivo Karlovic.
The fifth-seeded Swiss, now 11-1 all-time against the Croatian, was impeccable in the opening set, losing his only point on serve as he stood 5-4, 40-0 moments before serving out the opener.
A winning tie-break in the second finally made the difference for Federer, now 42-12 in Miami with titles in 2005 and 2006.
“I made sure I had a lot of first serves in, made sure I stayed aggressive from the baseline,” Federer said. “I think it worked really well, hardly any unforced errors.
“I was able to move Ivo around and I was able to maintain that throughout the match, which was key. I could focus a bit on returning while then holding serve, which is important against Ivo.”
Federer missed the tournament a year ago as he rested with back pain but has turned his 2014 season around after a low-key 2013.
Last weekend’s finalist at Indian Wells withstood 13 aces from the big-hitting Croatian in Friday's 74-minute win.
Spanish fourth seed David Ferrer made a winning comeback after missing Indian Wells with injury, defeating Russia’s Teimuraz Gabashvili, 6-4, 6-0.
French ninth seed Richard Gasquet reached the third round by beating Alejandro Gonzalez of Colombia 7-6 (9/7), 6-4.
China’s Li Na reached the third round in the women’s tournament after Russia’s Alisa Kleybanova withdrew from their tie with a viral illness.
The result sent the second seed into a contest against US teenager Madison Keys who put out Slovak 31st seed Daniela Hantuchova, 6-4, 6-2.
Two other seeds lost in upsets as American Varvara Lepchenko put out seventh seeded Jelena Jankovic 6-3, 2-6, 7-6 (7/2) and Czech Barbora Zahlavova Strycova beat Italian number 13 Roberta Vinci, 6-4, 2-6, 7-5.
Australian Open finalist and 10th seed Dominika Cibulkova defeated Yvonne Meusburger of Austria 6-1, 6-2.
