
Serena Williams is all smiles after she beat Russia's Ekaterina Makarova 6-3 6-3 in their first round match. Williams is bidding for a record 23rd grand slam singles title.

Fresh from claiming an Olympic silver medal, Juan Martin del Potro was in action on Tuesday. The Argentine eased through against compatriot Diego Schwartzman 6-3 6-3 7-6 (7-3).

Del Potro's vanquisher in Rio, Andy Murray was also untroubled in his opening match beating Lukas Rosol of the Czech Republic 6-3 6-2 6-2.

The players may have struggled in the searing heat -- temperatures were again tipping 30˚C on Tuesday -- but fourth seed Agnieszka Radwanska wasted little energy in her opening match brushing aside American Jessica Pegula 6-1 6-1.

It was a similar story for Romania's Simona Halep -- a semifinalist in 2015 -- as she defeated Kirsten Flipkens of Belgium 6-0 6-2.

Venus Williams, however, was made to work hard for her victory over Kateryna Kozlova of Ukraine eventually winning through 6-2 5-7 6-4.

Eleventh seed, Carla Suarez Navarro of Spain completed a double bagel -- 6-0 6-0 -- victory over Teliana Pereira of Brazil on Tuesday.

Canada's Eugenie Bouchard crashed out in three sets (6-3 3-6 6-2) to Katerina Siniakova of the Czech Republic.

Switzerland's Stan Wawrinka served up a 7-6 (7-4) 6-4 6-4 win over Fernando Verdasco of Spain.

Verdasco's compatriot David Ferrer had more luck in his opening round match, progressing against Alexandr Dolgopolov after the Ukrainian was forced to retire before the end of the first set.

Japan's Kei Nishikori, seeded sixth, shakes hands with Benjamin Becker after beating the German 6-1 6-1 3-6 6-3 on Tuesday.