Two friends from California, Learner Tien and Alex Michelsen, have both reached the fourth round at the Australian Open. Tien is 19, and Michelsen is 20.

American qualifier Learner Tien became the youngest man to reach the Australian Open fourth round in 20 years as he beat an ailing Corentin Moutet 7-6(10) 6-3 6-3 on Saturday, continuing the teenager's fairytale run at Melbourne Park.

Two of four American men still playing in Melbourne, Irvine native Tien, 19, and Aliso Viejo native Michelsen, 20, became friends on the youth tennis circuit