Miami - Andy Murray backed up a Davis Cup victory over Donald Young with a brisk 6-4, 6-2 win over the American on Friday to open his bid for a third Miami Masters crown.
Murray, seeded third, has defeated Young in five of six meetings, including last month's Davis Cup first-round date in Glasgow.
The Scot, who won titles at the town he uses as a training base in 2009 and 2013, mustered just 14 winners and hit 21 unforced errors, but it was enough compared to the 32 unforced errors from Young in the match played in draining heat and humidity.
The victory took less than 90 minutes and put Murray into a third-round meeting with Colombia's Santiago Giraldo, who beat Robin Haase of the Netherlands 6-2, 3-6, 6-0.
"I've played well against him the last couple of times, today was a very different match to Davis Cup - completely different conditions," Murray said.
"The heat was OK and the wind obviously cooled you down a little bit at the end changes. Sometimes it can be ridiculously hot, and that makes managing the points and your emotions (tough).
"It was just very tough weather to play good tennis in. So I just tried to play smart, and it worked."
Murray, a former Wimbledon and US Open champion, too his record in Miami to 23-7.
He powered to a 5-1 lead in the opening set, closing it out on the first of three set points, and led 5-2 in the second, putting the match away on Young's forehand error.
As seeded men in the combined WTA and ATP event swung into action after first round byes, eighth seeded Czech Tomas Berdych advanced with a 6-3 6-4 victory over South Korea's Chung Hyeon.
South African 15th seed Kevin Anderson defeated American Sam Querrey 6-7 (5/7), 7-6 (7/3), 6-4.
Australian Bernard Tomic shook off effects of last week's wisdom tooth trouble and back pain at Indian Wells -- which forced him to forfeit a match - posting a 7-6 (8/6), 7-5 victory over American Austin Krajicek.
Women's third seed Simona Halep pulled herself together after dropping the second set to earn a 6-4, 2-6, 6-1 victory over Czech Nicole Vaidisova.
The Romanian, who won the biggest title of her career on Sunday when she lifted the WTA premier level trophy at Indian Wells, was stunned in the second set by the 25-year-old Vaidisova, who retired in 2010 but is now making a return to the WTA which began late last year.
Although Halep was broken while serving for a three-set win at 5-0 in the third, she promptly broke back to secure victory in 92 minutes with 17 winners and 27 unforced errors.
Swede Johanna Larsson surprised Czech 10th seed Lucie Safarova with a 7-6 (7/5), 6-2, while teenaged American Catherine Bellis took revenge for a US Open defeat by beating Zarina Diyas 6-2, 6-1.
Bellis, 15, is ranked 211th and says she won't make a decision about turning pro until she cracks the top 100.
Italian Camila Georgi defeated Belgium's Alison Van Uytvanck 6-3, 6-2 while Russian Svetlana Kuznetsova overcame Alison Riske 6-2, 6-2 and Spain's Garbine Muguruza beat Sesil Karatantcheva 6-1, 6-3.