British No 2 Heather Watson suffered a first-round exit at the Miami Open by Brazil's Beatriz Haddad Maia.
Watson, ranked 72 in the world, went down 7-6 6-2 in one hour and 36 minutes to the world No 64.
Watson had edged 5-4 ahead in a tight first set but was unable to retain that advantage as Haddad Maia hit straight back and then won a tie-break.
She then broke early in the second set and Watson could not recover.
British No 1 Johanna Konta, the defending champion, was not in action having been awarded a bye into the second round. She will face Kirsten Flipkens in the first match after the Belgian triumphed 6-2 6-3 against Mihaela Buzarnescu after an hour and 18 minutes on court.
Katie Boulter claimed a place in the main draw by coming from behind to beat Carol Zhao of Canada 3-6 7-6 6-2 in her final qualifier.
Cameron Norrie and Liam Broady also secured spots in the first round of the men's event.
Norrie beat American Patrick Kypson 6-7 6-3 6-1 while Broady saw off Canada's Filip Peliwo 6-4 7-6 (7-2).
You can watch more ATP Masters 1000 action from the Miami Open when we return on Sky Sports Arena next Wednesday at 3pm.
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