World number one Iga Swiatek maintained her impressive form by seeing off Aryna Sabalenka in straight sets in Sunday's Stuttgart Open final to win a fourth straight WTA title.

Swiatek was made to work hard in Saturday's semi-final against Liudmila Samsonova as she dropped a rare set, but she was back to her imperious best against Sabalenka.

The 20-year-old prevailed 6-2 6-2 in 84 minutes to make it 23 victories in a row – only five other different players have enjoyed longer winning runs since 2000.

With her latest triumph in Germany, Swiatek has now won 30 WTA matches in 2022, compared to 36 in the whole of 2021.

She has won the Qatar Ladies Open, Indian Wells and Miami Open in straight succession, having also reached the semi-finals of the Australian Open in January.

Iga Swiatek has won 23 matches in a row

Sabalenka, who eliminated Paula Badosa, Anett Kontaveit and Bianca Andreescu en route to the final, was the latest player to fall short in trying to stop the sublime Swiatek.

After saving a break point in the opening game, Swiatek held serve and broke her opponent in the next game before comfortably seeing out the first set.

The Pole never looked under serious threat in the second set as she took the last four games to down world number four Sabalenka, who lost to Ash Barty in this final last year.

At the Istanbul Cup, meanwhile, Anastasia Potapova beat Veronika Kudermetova 6-3 6-1 to clinch her maiden career title.

Qualifier Potapova recovered from a set down to beat Yulia Putintseva in Saturday's semi-final and was too strong for Kudermetova in what was her third career final.

Kudermetova broke Potapova early on and led 3-1 in the opening set, but the latter soon found her range and took advantage of some sloppy mistakes from her opponent.

After battling to victory in the first set, Potapova looked far more comfortable in the second as she produced a number of impressive shots en route to a breakthrough triumph.