- Watson loses 7-5 3-6 6-4 to 13th seed Kerber
- Serena Williams beats Niculescu in straight sets
- Novak Djokovic through in three sets
- Murray v Giraldo at 16:00 BST, Sunday
Britain's Heather Watson could not complete a dramatic comeback against Angelique Kerber as the German won their rain-delayed Miami Open contest.
Watson, ranked 41st, recovered from 5-1 down in the final set only to drop serve when trying to level at 5-5, eventually losing 7-5 3-6 6-4.
The second-round match was suspended because of bad weather on Friday with Kerber, the 13th seed, leading 7-5.
Defending champions Novak Djokovic and Serena Williams both went through.
Watson rues missed opportunity
The 22-year-old Briton had been hoping to build on her impressive run to the fourth round of Indian Wells two weeks ago but came up just short against Kerber.
Watson had let a 5-3 lead and two set points slip by in the first set on Saturday and ended the match having earned 20 break points, but converted only seven.
After getting the better of five breaks in the second set, Watson looked to have blown her chance when she slipped a double break down in the decider.
Kerber, 27, appeared to be fading badly as she twice failed to serve out the contest, only for Watson to let her off the hook with four errors when serving at 5-4 down.
Asked about having to play across two days in testing conditions, Watson told BBC Sport: "I'm not a stranger to it; I think it gave me a good opportunity after losing that first set to regroup.
"I think I didn't strike the right balance today in when I should be patient and when I should be aggressive.
"I'm very disappointed in today. I felt it was a good opportunity for me, but I feel like I'm definitely improving as a player on the court with my tennis and mentally.
"I know I can compete with these girls and push them and beat them."
Serena puts knee issue behind her
Top seed Serena Williams beat Monica Niculescu 6-3 6-1, the American enduring some frustrating moments as she overcame the unorthodox Romanian for the second tournament running.
Williams had been a doubt for Miami with a knee injury, but said: "It was a little sore in practice, but it was OK today. I really didn't feel it today, to be honest."
Canadian sixth seed Eugenie Bouchard suffered a surprise 6-0 7-6 (7-4) defeat by Germany's Tatjana Maria.
Djokovic made to work for win
Men's top seed Novak Djokovic looked poised for a straightforward victory when he took the first set 6-0 in 23 minutes against Slovakia's Martin Klizan, the world number 41.
Djokovic won the first seven games and served for the match at 5-3 in the second.
But he dropped his serve and Klizan went on to level, before Djokovic re-established control and earned a 6-0 5-7 6-1 victory after one hour 56 minutes.
"I obviously felt great in the beginning of the match, and then in the opening three games of the second set I made two double faults and got him into the match," the 27-year-old said.
"I did drop the level at the second set, but in the third I managed to bounce back and get a win."
Djokovic next plays Belgian qualifier Steve Darcis, a 6-4 6-7 (2-7) 6-3 winner over Gilles Muller.