Hello and welcome to our live coverage of the third and final match on day one of the WTA Championships featuring Maria Sharapova v Sara Errani in the White Group. Earlier, Serena Williams disposed of Angelique Kerber in straight sets, as did Agnieszka Radwanska against Petra Kvitova.

SHARAPOVA 6-3 6-2 ERRANI – GAME SET MATCH – Errani hits wide as Sharapova races to 30-0 but the Russian then hits long to prolong proceedings. Yet another forehand winner brings two match points and another forehand winner gives her victory in her opening match.

SHARAPOVA 6-3 5-2 ERRANI – Sharapova nets on the opening point and a cheeky drop shot puts the Italian further ahead. An outrageous net cord plops over to bring three game points and she holds as Sharapova hits long. Sharapova to serve it out.

SHARAPOVA 6-3 5-1 ERRANI –Sharapova opens with yet another winner, her 34th, and follows with another ace. She races to 40-0 with another forehand winner but throws in another double at 40-15 but blazes another winner to get to within a game of the match.

SHARAPOVA 6-3 4-1 ERRANI – BREAK – Some awesome hitting from Sharapova piles on the pressure and forces a nervy double fault. Another punishing forehand brings two more break points. Sharapova hits long on the first but a stunning backhand winner surely gives her the decisive double break.

SHARAPOVA 6-3 3-1 ERRANI – Sharapova opens with successive winners and races to 40-0 as Errani loops a defensive lob long. Another good serve wins the game to love. First love hold of the match.

SHARAPOVA 6-3 2-1 ERRANI – Errani looks on the ropes now as she nets on the opening point. Sharapova lets her off the hook with a wayward forehand and netted drive volley but another forehand winner restores parity at 30-30. Successive forehands go wide and Errani stays in touch. Just.

SHARAPOVA 6-3 2-0 ERRANI – Dogged retrieving wins Errani the opening point but she floats a backhand long then nets. A forehand drive volley and ace number five wraps up the game.

SHARAPOVA 6-3 1-0 ERRANI – BREAK – Sharapova opens as the ended the first set, some big hitting getting the Russian three immediate break points. A blazing backhand winner increases her stranglehold as she breaks to love. She has only lost one in 48 matches this year after winning the first set. Ominous.

Sharapova needs to win at least two group games and the tournament to have a chance of ending the season as world number one.

SHARAPOVA 6-3 ERRANI – SET – Sharapova opens with ace number three but she hits long. A successful challenge nets her ace number four and more big groundies bring up two set points for the Russian and a forehand winner takes the opener.

SHARAPOVA 5-3 ERRANI – Errani races to 40-0 but Sharapova replies with some big winners to pull the game back to deuce. A neat drop volley gives the Italian game point and she eventually holds on to force Sharapova to serve it out.

SHARAPOVA 5-2 ERRANI – Sharapova opens with a third double fault but more big hitting, including yet another forehand winner, gets the Russian two game points and she rounds it off with a second ace.

SHARAPOVA 4-2 ERRANI – BREAK – Sharapova receives some coaching in between games and she wins the opening point as Errani hits wide. Still the balls keep coming back as Sharapova struggles to break through the Italian’s defences but a backhand winner earns two more break points and a crunching forehand winner gives Sharapova a second break.

SHARAPOVA 3-2 ERRANI – Errani really beginning to warm to this and Sharapova looks frustrated with the amount of balls coming back. Brilliant retrieving again helps the Italian to 15-30 and Sharapova is guilty of over hitting to concede two break points. Big hitting from the Russian saves the day and she hangs on with a whipped forehand winner.

SHARAPOVA 2-2 ERRANI – Sharapova nets on the opening two points but she hits back with a forehand winner. Great retrieving from the Italian forces another Sharapova error but the Russian stays in the game with yet another clean forehand winner and Errani hits long as another game goes to deuce. A winning Sharapova return brings another break point but Errani again hangs tough to hold. It’s already an intriguing match up of power versus speed.

SHARAPOVA 2-1 ERRANI – BREAK – Great character from Errani. Yet another blazing forehand winner takes Sharapova to 30-0 as Errani is guilty of too many mid court balls. But a second double gets Errani on the board and Sharapova then nets an easy backhand. The Italian smacks a forehand winner of her own to bring up break point and she converts as Sharapova hits wide.

SHARAPOVA 2-0 ERRANI – BREAK - Errani races to 30-0 after two loose Sharapova returns but she is then rushed into an error on the forehand wing. A cute dropshot and lob brings the Italian two game points but another crunching Sharapova forehand winner and unforced error sees the second game to deuce. Sharapova saves another game point then brings up a break point of her own. Errani hangs tough to save another but Sharapova breaks through at the third time of asking.

SHARAPOVA 1-0 ERRANI – A tough opening hold for Sharapova. Errani nets on the opening point and Sharapova follows up with her first ace. The Italian wins her first point after a long baseline exchange and gets back to 30-30 after Sharapova hits long. Errani hits long but the Russian double faults as the game goes to deuce. A drive volleyed winner brings Sharapova’s first cry of ‘come on’ and she holds with another forehand winner.

Errani has won the toss and elected to receive, hoping for an early break.

The match is a repeat of this year’s French Open final where Sharapova came through a 6-3 6-2 winner in their only previous meeting. Don’t forget you can watch all the action from the WTA Championships in Istanbul on British Eurosport or online.