Germany’s grip on the crown continued in 2017, where Siegemund emerged as the surprise winner, beating Kristian Mladenovic in a thrilling final, 6-1, 2-6, 7-6(5). (Getty Images)

Stuttgart sensations: Champions from Petrova to Siegemund

Forehand - Jelena Ostapenko

Motion pictures: Jelena Ostapenko's WTA photo shoot

Elina Svitolina is the defending champion, having beaten Elise Mertens 6-2, 6-4 in the 2017 final (tournament)

Iconic in Istanbul: From Venus to Svitolina

France's Caroline Garcia was singles and doubles champion in Bogota in 2014 (Getty)

Clean sweep: Champions in singles and doubles at the same tournament

Already the oldest player to win a Grand Slam singles title, by capturing the 2017 Australian Open, Serena Williams passed Graf for most Grand Slam singles titles won in the Open Era – 23

Celebrating 50 years of the Open Era

Forehand - Simona Halep

Motion pictures: Simona Halep's WTA photo shoot

Smile - Karolina Pliskova

Motion pictures: Karolina Pliskova's WTA photo shoot

Doubles World No.1 Latisha Chan reached the Sydney final with new partner Andrea Sestini Hlavackova this year

Top 10 doubles players and their best 2018 result

Smile - Elina Svitolina

Motion pictures: Elina Svitolina's WTA photo shoot

World No.5 Jelena Ostapenko. Lost the final of the Miami Open to Sloane Stephens 7-6, 6-1 (Getty)

The Top 10: Rankings leaders and their 2018 best result

Casey, pictured with players from the Carlton Blues football club during the 2004 Australian Open, quickly proved a popular addition to the tour (Getty)

Casey Dellacqua retires: A stellar career in photos

Francesca Schiavone was the 2017 champion, beating Arruabarrena in the final (tournament)

Brilliant in Bogota: From Duque-Mariño to Schiavone