Eighteen-time grand slam champion Martina Navratilova said that Simona Halep must get out of her comfort zone if she wants to emerge victorious against Maria Sharapova when the two meet at the Singapore Indoor Stadium today as this year’s edition of the WTA Finals continues.

With Serena William’s absence in Singapore, Navratilova said that Halep is the favourite to win the WTA Finals title, Sport 360 reports. However, the Romanian must face up to the challenge of the Russian tennis star and set goals to win against Sharapova. Even though the conditions in Singapore suits Halep, Navratilova said that the Romanian tennis star should not feel too relaxed.

“She (Halep) needs to stay with the defence when it calls for it, but still make herself get inside the court more and not let Maria dictate,” Navratilova said. “Because Maria will be playing better and better as the week goes; she is fresh, she’s happy to be here, she’s healthy finally, so she’s not feeling any pressure, so Simona needs to, I think, get out of her comfort zone a little bit and get closer to the baseline.”

Navratilova is an eighth-time champion at the WTA Tour Championships. She is in Singapore for this year’s WTA Finals’ Legends Classic event.

Sharapova and Halep have one win under their belt after scoring victories against Agnieszka Radwanska 4-6 6-3 6-4 and Flavia Pennetta 6-0 6-3 on Monday, respectively. Sharapova needed nearly three hours to get past Radwanska, while Halep only needed one hour and 10 minutes to win her first match in Singapore.

The Russian has a 5-0 advantage over Halep. Sharapova had only dropped three sets against Halep when the Romanian pushed their last three meetings to three sets, including Sharapova’s most recent win during the quarterfinals of the 2014 Cincinnati Open, 3-6 6-4 6-4.

Meanwhile, Radwanska and Pennetta will headline the first match of Red Group today. Radwanska leads their head-to-head series 5-3. It will be their second meeting this year after the duo played in the round 16 of the Qatar Total Open, where the Polish won 6-1 6-1.

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