Former world number one Angelique Kerber delayed her retirement from tennis again when she outlasted Romanian Jacqueline Cristian 6-4, 3-6, 6-4 in the second round at the Paris Olympics on Monday. Urged on by fans chanting her name, the three-time grand slam champion from Germany prevailed after 2 hours 16 minutes in sweltering mid-day heat at Roland Garros on a third match point. Kerber, 36, who returned in January from maternity leave, said last week that she will end her career after the Olympics, where she will also play doubles with Laura Siegemund. She won a duel of former world number o…