US Open: Home hopes hit as Madison Keys makes 89 unforced errors in first-round loss

• Australian Open champion beaten by Renata Zarazua

• World No 6 suffers string of errors in loss

One of the main home hopes at the US Open has suffered an early exit from the tournament after Madison Keys lost in the first round on Monday.

There were early signs the world No 6, who won the Australian Open in January, faced a tough match against Mexico's Renata Zarazua. The American won the first set, but only after taking a marathon tiebreak 12-10. Zarazua won the second set on another tiebreak (7-3) before closing out the match by taking the final set 7-5.