Coco Gauff digs deep to survive Ajla Tomljanović test in US Open marathon

• No 3 seed overcomes 10 double faults in opener

• Gauff edges Tomljanovic 6-4, 6-7, 7-5 in 2h57m

• World No 1 ranking still within American's grasp

Coco Gauff survived a shaky serving performance to battle past Ajla Tomljanovi in the first round of the US Open, winning 6-4, 6-7 (2), 7-5 after 2hr 57min on Tuesday night.

The No 3 seed finished with 10 double faults, was broken six times and squandered a string of opportunities to close the contest earlier, but conjured enough resilience to scrape into round two under the lights on Arthur Ashe Stadium.