ZHUHAI, China - No.2 seed Anastasija Sevastova sealed her first match at the 2018 Hengqin Life WTA Elite Trophy Zhuhai in style, edging past Chinese wildcard Zhang Shuai in a straight sets thriller.

After notching the perfect start, winning the opening set to love, Sevastova had to fight through an inspired comeback effort to defeat Zhang 6-0, 7-6(10) after a rollercoaster hour and 28 minutes.

"I think it's tough playing on Thursday," Sevastova told press afterwards. "I was here from, like, Saturday. Not playing for so many days, just practicing, for her for sure was easier.

"I started very well. I really didn't think I would start so well. In the first set, she also gave me a lot of points. In the second… I think I let her in. It was my mistake.

"I was not concentrated. I was not focused. I was lucky that I escaped in the second set in a tiebreak anyway, because normally it's a third set."

The victory means that former semifinalist Sevastova is one step closer to returning to the final four in Zhuhai. But standing in her way will be nemesis Garbine Muguruza, who rounds out the Camellia Group with Zhang and Sevastova. Having suffered two defeats, Zhang is out of contention - which means the Camellia Group's semifinal spot will come down to either Sevastova or Muguruza, who are set to clash tomorrow for the fourth time.

Anastasija Sevastova [Photo courtesy WeChat account:WTA_Tennis]

Beijing finalist Sevastova posted a nearly untouchable performance in the opening set, winning all 12 points across her three service games - claiming 100% of first serves and second serves. As a result, she didn't face break point at all, and Zhang shouldered all the pressure.

Sevastova broke to start the first set after a marathon game, notching a 1-0 start, and then she struck again two games later, converting her third break point to claim another lengthy game and extend her lead to 3-0. She didn't look back from there, reeling off the next three games in a row to complete the shutout.

But it was a completely different story in the second set as Zhang rode the enthusiastic wave of Chinese support from the Zhuhai crowd to an inspired comeback effort. The fans roared as Zhang finally got on the scoreboard at 1-0, stopping the run of six consecutive games from Sevastova.

The Latvian came out on top after a spate of three straight breaks of serve left her ahead at 3-2, and had three chances to extend her at 4-3, Zhang holding firm to deny her the break points. Sevastova served for the match at 5-4, and was two points from victory when Zhang finally broke back.

They were neck and neck heading into the tiebreak, but it was Zhang who pulled away to a fast 5-1 lead. Sevastova didn't stay down for long, denying Zhang six set points in total as she turned around the score. The Latvian finally converted her second match point to seal the victory after a tightly contested hour and a half of play.

The victory also marks a personal best for Sevastova: in addition to securing her 43rd WTA main draw win of the year (her previous highest number of wins was 37 in 2017) she also recorded her 25th win of the year on hardcourts - the most hardcourt wins she's ever recorded in a single season.

She'll look to grow that number in her clash against Muguruza tomorrow as the pair battle it out for the last Camellia Group spot.

"Muguruza is a tough opponent," Sevastova acknowledged. "She puts you under a lot of pressure. I saw the last match which she played against Shuai. It's going to be tough for me and I know she's going to go for it.

"I have to move. I have to serve better because she's going for the returns. When she goes to the net, she's not afraid of playing in the net and finishing the points, making it faster and shorter.

"Yeah, I have to play my game. I have to play like I did in the first set."