Andy Murray, who claimed his second title of the season in Vienna last week, defeated Austria's Jurgen Melzer 6-3, 6-3.
John Tomic, who also coaches Bernard, is barred from tournaments by the ATP and International Tennis Federation.
Melzer was leading 6-3, 2-1 -- and was up a break in the second set -- when Monfils called it quits with an abdominal muscle injury.
The French 15th seed defeated 10th-seeded Ukrainian Alexandr Dolgopolov 7-6 (11/9), 6-3 while Jurgen Melzer defeated
Fognini led 4-1 before dropping serve in the third. He held on and became the first Italian champion in Stuttgart.
Andy Murray breezed past Spanish veteran Tommy Robredo, the 32nd seed, 6-2, 6-4, 7-5. Sergiy Stakhovsky, the world number 116, who sent seven-time champion Federer crashing out in the second round, went down 6-2, 2-6, 7-5, 6-3 to experienced Austrian Jurgen Melzer.
After the highs of beating Roger Federer at Wimbledon, Stakhovsky was brought back down to earth after he slumped to a 6-2, 2-6, 7-5, 6-3 loss to Jurgen Melzer.
Stakhovsky, who became an Internet hit last month for whipping out his mobile phone to take a photo of a controversial line call on the clay of the French Open, has four tour titles to his name. He was also 31 in the world three years ago.
Mahesh Bhupathi-Julian Knowle beat Argentine-Spanish duo Leonardo Mayer and Albert Ramos 6-2, 6-7(5), 6-4, 6-2 in two hours and 37 minutes in the first round clash.
Seeded ninth, Paes and Melzer fought hard before going down 7-5 4-6 6-7(6) against unseeded Uruguan-Argentine duo of Pablo Cuevas and Horacio Zeballos in little less than two-and-a-half hours at the Roland Garros.