Agnieszka Radwanska has lost just two of her nine previous meetings with Jelena Jankovic, and beat the Serb in the last 16 at Wimbledon two years ago.
Jankovic is appearing at Wimbledon for the 14th successive year, and her 55th consecutive Slam main draw showing is not beaten by any other active player.
Irina Falconi has fallen at the first-round stage at Wimbledon four times in the last six years and has lost 10 of her 19 Slam openers.
Victory would help Karolina Pliskova rejoin Elina Svitolina at the top of the match-win list for 2017 (37) – Kristina Mladenovic can also achieve that mark today.
Mladenovic has won 13 of her 23 meetings with fellow Frenchwomen, ahead of her clash with Pauline Parmentier today. Her 36 wins in 2017 is already five more than she managed in the total of 2016.
After making three Slam finals in 2016, World No.1 Angelique Kerber has failed to reach the last eight of either Slam so far this year. She hopes to avoid successive Slam first-round exits for the first time since 2011, while defeat today would also make her the first top seed to lose in the first round since Martina Hingis, back in 2001.
Garbiñe Muguruza is the only currently active player to beat Kerber at Wimbledon in three years.
Former World No.1 Caroline Wozniacki is making her 11th main draw appearance at Wimbledon, but the tournament remains the only Slam where she has failed to reach the last eight.
Timea Babos hopes to make the third round of a Slam for just the second time in what is her 20th Slam.
Ons Jabeur is only the second Tunisian woman to ever win a Slam match, following Selima Sfar.
Svetlana Kuznetsova is making her 59th Slam appearance – only six currently active players have made more in the main draw.
Christina McHale faces a British opponent at Wimbledon for the second time – having beaten Johanna Konta in the opening round five years ago. The American is yet to make it past the third round at SW19 – this is her seventh year at the tournament.
Coming into the tournament in form following her victory in Eastbourne last week, Karolina Pliskova has the chance to assume the world No.1 spot with a good showing at Wimbledon. We detail exactly what the Czech requires to overtake Angelique Kerber at the top.
Laura Robson was the first Briton to exit at this year's tournament. Read the Daily Mail's take on events.
Read our report as second seed Simona Halep made a comfortable start to her campaign.