Iga Swiatek of Poland on Monday defeated Jessica Pegula of the United States 6-1 6-0 to win the Women’s Tennis Association (WTA) Finals in Cancun, ending the season by reclaiming her world number one ranking from Belarus’ Aryna Sabalenka.

In a match postponed by a day due to rain, the Pole defeated Pegula five times and won the last 11 games in a 59-minute slaughter to win her first WTA Finals title.

“I want to thank my team who have been with me for the whole season,” Swiatek said during the trophy ceremony.

“We’ve had many ups and downs but this is for sure an up, and we’ll have many more if we keep working like that.”

She also thanked the fans who endured countless rain delays and gusting winds over the course of the event at the coastal Mexican resort town.

“Thank you, guys, for coming and cheering for us, you really made it special,” she said. “Thank you for all these Polish flags and Polish people who are coming to every tournament and those from many countries. Every year I feel like I have more and more support.”

Swiatek, who won the China Open last month, ends the season with an 11-match winning streak and will finish the year in the top spot for the second year in a row, having lost the position to Sabalenka after the US Open.

Swiatek, 22, collected six out of her total 17 career titles this season. She retained the French Open crown in June to lift her fourth Grand Slam trophy, Reuters reported.

The 29-year-old Pegula, who struggled on her serve and failed to match Swiatek’s energy level, was gracious in defeat.

“Congrats on ending the year number one and winning this tournament, it’s really incredible,” she said.

“You continue to push me to be a better player and I appreciate that aspect of it. I wish I could have done better today but that’s not how it goes sometimes.”