Elena Rybakina moved into the semi-finals of the Miami Open with a confident 6-3, 6-0 win over Italy's Martina Trevisan at Hard Rock Stadium on Tuesday to extend her winning streak to 12 matches.

American world number three Jessica Pegula had to dig deep to come back from a set down to beat Russian Anastasia Potapova 4-6, 6-3, 7-6 (7/2), saving two match points, in a match which finished at 1:30 am.

Wimbledon champion Rybakina, who competes for Kazakhstan, remains in strong contention for the "Sunshine Double" of Indian Wells and Miami WTA titles after she beat Aryna Sabalenka in California earlier this month.

Sabalenka is the biggest obstacle to Rybakina triumphing again with the Belarusian in impressive form in South Florida.

Sabalenka powered past Barbora Krejcíkova in straight sets in her fourth-round match on Monday and faces Romanian Sorana Cirstea in the last eight on Wednesday.

Rybakina took charge of her match with Trevisan when the Italian double-faulted to hand her opponent a break and a 3-1 advantage in the first set.

Although Trevisan broke back to get back on serve at 4-3, Rybakina took full control and won the remaining eight games to wrap up the win in 69 minutes.

The world number seven said she was feeling the pace of her tough schedule.

"It would be better to feel better on the courts physically, but this is something I have to play with, and for now I am getting through, which I'm happy with," she said.

"I didn't serve that well, the percentage of the first serve, but in the important moments like 30-all, 30-40 and so on, I was serving aces," added the Moscow-born player.

"I think it's just important to find these moments and to push, and for now I'm doing well even not being super fresh."

Pegula has got off to flying starts in her matches in Miami and she broke early again to go 2-0 up in the first set, but Potapova struck back winning the next five games with some aggressive winners and then holding to take the set.

Pegula was in control in the second but Potapova was determined in the third and put herself in position to win the contest but she couldn't convert on her two match points and was forced into a tie-break.

The American looked exhausted, but she found the energy for a strong finale, winning the breaker 7-2.

"I don't know how I turned it around," said Pegula after the victory.

"I just kept going. It's a huge win. I haven't been that physically tired in a really long time. Just the humidity was taking so much out of me. It was just really tough, so really it was just pure will," she added.

Pegula will have a day off before she has to face Rybakina and she says she is relishing the chance.

"She's been playing some great tennis, I feel like her and Sabalenka are the ones to beat right now. It is going to be a great test and I think it is a deserved semi for a tournament like this," she said.