WTA Finals: Flavia Pennetta, Maria Sharapova grind out gritty victories

Russia's Maria Sharapova hitting a return to top seed Simona Halep of Romania during their WTA Finals match at the Singapore Indoor Stadium on Oct 27, 2015.
Russia's Maria Sharapova hitting a return to top seed Simona Halep of Romania during their WTA Finals match at the Singapore Indoor Stadium on Oct 27, 2015.ST PHOTO: CHEW SENG KIM
Romania's Simona Halep reaches for the ball in the match against Russia's Maria Sharapova in the WTA Finals match at the Singapore Indoor Stadium on Oct 27, 2015.
Romania's Simona Halep reaches for the ball in the match against Russia's Maria Sharapova in the WTA Finals match at the Singapore Indoor Stadium on Oct 27, 2015.ST PHOTO: CHEW SENG KIM
Flavia Pennetta of Italy hitting a return to Agnieszka Radswanka of Poland during their WTA Finals match at the Singapore Indoor Stadium on Oct 27, 2015.
Flavia Pennetta of Italy hitting a return to Agnieszka Radswanka of Poland during their WTA Finals match at the Singapore Indoor Stadium on Oct 27, 2015.ST PHOTO: CHEW SENG KIM
Flavia Pennetta of Italy hits a return to Agnieszka Radswanka of Poland during their women's singles tennis match at the WTA Finals at the Singapore Indoor Stadium on Oct 27, 2015.
Flavia Pennetta of Italy hits a return to Agnieszka Radswanka of Poland during their women's singles tennis match at the WTA Finals at the Singapore Indoor Stadium on Oct 27, 2015. PHOTO: REUTERS
Poland's Agnieszka Radswanka hits a backhand shot to Flavia Pennetta of Italy during their WTA Finals match at the Singapore Indoor Stadium on Oct 27, 2015.
Poland's Agnieszka Radswanka hits a backhand shot to Flavia Pennetta of Italy during their WTA Finals match at the Singapore Indoor Stadium on Oct 27, 2015. ST PHOTO: CHEW SENG KIM
Italy's Flavia Pennetta (left) shaking hands with Poland's Agnieszka Radwanska after defeating her 7-6(5), 6-4 at the WTA Finals at the Singapore Indoor Stadium on Oct 27, 2015.
Italy's Flavia Pennetta (left) shaking hands with Poland's Agnieszka Radwanska after defeating her 7-6(5), 6-4 at the WTA Finals at the Singapore Indoor Stadium on Oct 27, 2015. ST PHOTO: CHEW SENG KIM

SINGAPORE - Playing the last Tour event of her professional career, Flavia Pennetta sure is not in Singapore just to make up the numbers.

The Italian rallied to beat Agnieszka Radwanska 7-6 (7-5), 6-4 on Tuesday afternoon at the Singapore Indoor Stadium, keeping herself in contention for a spot in the semi-finals of the BNP Paribas WTA Finals Singapore presented by SC Global.

Twice a break down in the first set, Pennetta, the world No. 8 and reigning US Open champion, turned up the heat, with her potent backhand her frequent weapon of choice in the match. She was 3-5 against world No. 6 Radwanska before the match.

Pennetta is making her debut appearance at the WTA Finals, but lost her first match against Simona Halep on Sunday when she was trounced 6-0, 6-3.

The result keeps her hopes of making it past the group stages alive, but neither is it all over for Radwanska. This, after Maria Sharapova handed top seed Simona Halep a defeat, winning 6-4, 6-4.

Said the Russian world No. 4 after her second straight win: "It got really tough and those are the moments you have to get through when you haven't played in a long time. Especially against the world No. 2, these matches don't come easy and it showed in the end."

The results extends Sharapova's record against the Romanian to 6-0.

While Sharapova is the only undefeated player in the Red Group, she is yet to be guaranteed a place in the semi-finals. It will come down to the players' final round-robin matches on Thursday.