NEW YORK, Sept 5 (Reuters) - Leylah Fernandez has had a great start to her career and the teenager has a big future ahead of her, former champion Angelique Kerber said on Sunday after losing 4-6 7-6(5) 6-2 to the Canadian at the U.S Open. Fernandez, who turns 19 on Monday, knocked out defending champion Naomi Osaka in the third round and then reached a Grand Slam quarter-final for the first time with her win over the German. "If she plays like this, consistently plays the whole year, the next tournaments like this, the next rounds, I think she has a great future," Kerber told reporters. "She has a lot of power in her forehand and she"s going for her winners. I think she"s always also enjoying her tennis out there, it was a tough match. I think she can go really far in the next few years." Kerber, who won the 2016 title at Flushing Meadows, said Fernandez"s tactics reminded her of herself, especially her approach on serve and the next ball. "I have been through a long career with a lot of up-and-downs," the 33-year-old added. "It"s just experience you have to go through. "Of course when you reach your first quarter-finals in a Grand Slam, it"s always a lot of emotions. She had nothing to lose today and I think she"s enjoying her tennis ... it"s just a start of a great career." Fernandez faces fifth seed Elina Svitolina in the quarter-finals.