Maria Sharapova's comeback continues with straight sets win over Ekaterina Makarova at the Stuttgart Open

Sharapova defeated Makarova 7-5, 6-1 and will play rising star Anett Kontaveit of Estonia for a place in the semi-finals of the Porsche Grand Prix

Victory guaranteed Sharapova a ranking inside the top 400 (Getty)

Former World No 1 Maria Sharapova defeated her fellow Russian Ekaterina Makarova 7-5, 6-1 on Thursday afternoon, to progress into the quarter-finals of the Porsche Grand Prix.

Playing in just her second match since returning from a 15-month doping ban, Sharapova looked far more assured than in her victory over Tour veteran Roberta Vinci on Wednesday evening.

The Russian hit nine aces and held her serve throughout, converting three of her four break points to win in style.

Sharapova's comeback continued with a routine win over Makarova (AFP/Getty)

As opposed to her eagerly-awaited return against Vinci, Sharapova started her Round of 16 match on Centre Court at the Porsche-Arena at a lightning pace.

She won her first two service games without losing a single point although – as in her match against Vinci – she struggled with her return of serve, and in particular with her court positioning.

Makarova, ranked a lowly 45^th in the world but coming into the match of an impressive straight set win over the former Wimbledon finalist Agnieszka Radwańska, also started impressively, and she looked to take advantage of Sharapova’s lack of match fitness by effectively mixing up her shots during the long baseline rallies.

But she paid the price for failing to take her only break opportunity, with the score locked at 5-5 in the first set. A steely-faced Sharapova defended well, before capitalising on a break point of her own with a crunching crosscourt forehand winner in the next game.

The second-set was a mere procession, with Sharapova breaking twice to race into a commanding 5-1 lead. She won the match with a thumping ace, for her second win in as many days.

Sharapova will now play against Anett Kontaveit of Estonia for a place in the semi-finals. Aged just 21, Kontaveit is a rising star of the Tour who defeated reigning French Open champion Garbiñe Muguruza in the Round of 16.

Rising star Kontaveit stunned Muguruza (Getty)

Sharapova’s victory over Makarova means that, after entering the tournament without a ranking, she is now guaranteed a spot inside the top 400. Should she beat Kontaveit she will seal a spot in the top 300, with a title guaranteeing her a top 125 ranking.

Meanwhile, Anastasija Sevastova beat sixth-seeded Johanna Konta 6-3, 7-5 to set up a quarterfinal match against Simona Halep, who last week beat Konta in the Fed Cup.

Laura Siegemund, a finalist last year, defeated the 2009 champion Svetlana Kuznetsova 6-4, 6-3, and Carla Suarez-Navarro beat Elena Vesnina 6-2, 6-4.