US Open champion Sloane Stephens beat Latvian Jelena Ostapenko 7-6 (7-5) 6-1 to win her first Miami Open title.
American Stephens looked tense at the start and there were eight breaks of serve in the first set before the home favourite prevailed in the tie-break.
The 25-year-old world number 12 relied heavily on her defence before putting her foot on the gas in the second set.
World number five Ostapenko, 20, was left to rue an unforced error count of 48 which cost her a first win in Miami.
It was the first ever meeting between the pair, both Grand Slam winners in the past 12 months, and their nerves showed in the opening exchanges as the first four games went against serve.