Former world number one Angelique Kerber saved two match points as she claimed a first victory since her return from maternity leave, 4-6, 6-2, 7-6 (9-7), over Ajla Tomljanovic in the United Cup semi-finals on Saturday. Kerber’s victory in 2 hours 34 minutes in Sydney gave Germany a 1-0 lead over hosts Australia. But the tie will be decided in the concluding mixed doubles, after Alex de Minaur levelled at 1-1 by handing Alexander Zverev a first defeat of the tournament, 5-7, 6-3, 6-4. De Minaur had earlier in the week also won against world number one Novak Djokovic. Kerber failed to serve out…