Hello and welcome to our LIVE coverage of the Group B match between Roder Federer and Juan Martin Del Potro from London’s O2 Arena.

Federer 6-7 6-4 3-6 – GAME SET MATCH DEL POTRO! Federer again hits long and Del Potro fires down an eighth ace to go 30-0 ahead. He nets a simple forehand to give Federer some hope but the Swiss again hits long to concede two match points. And he gets there at the first time of asking, Federer netting a tough volley. Thanks for joining us. I’ll be back at the same time tomorrow for the first semi final. Tweet me @fmasefield.

Federer 6-7 6-4 3-5 – Federer opens with a deft volleyed winner but then throws in a first double fault. A delightful drop shot winner edges the Swiss ahead again and he knocks off a volley and sends down an ace to force Del Potro to serve out for the match and a place in the semi final.

Federer 6-7 6-4 2-5 – Federer is fired up after winning his first point on the Del Potro serve for 23 minutes but the Argentine responds with a similar forehand winner to restore parity. Federer screams at himself for netting a backhand. Another ace and netted Federer forehand and Del Potro is a game away.

Federer 6-7 6-4 2-4 – Federer wins the opening two points but mutters angrily to himself after sending a backhand long. He has another go at himself after shanking a backhand wide. It does the trick and two aces save the day.

Federer 6-7 6-4 1-4 – Del Potro successfully appeals for an ace and Federer then hits long to go 30-0 down. Del Potro hits a winning pass and a big serve gives him a three game cushion. Crunch time for Federer now.

Federer 6-7 6-4 1-3 – Federer looks to be a little rattled as he floats a sliced backhand into the net. He follows it with a backhand winner and Del Potro is exasperated to push a ball wide that should have been an easy winner. The Argentine nets and Federer serves an ace to stay in touch.

Federer 6-7 6-4 0-3 – Del Potro opens his shoulders with a big forehand winner to start the game and another rushes Federer into a mistake. The Swiss twice nets and Del Potro holds to love. Strong favourite now.

Federer 6-7 6-4 0-2 – BREAK! The second game also opens with a successful challenge against the same line judge and the point is replayed. The same judge follows with two correct ‘out’ calls as Federer wins the opening two points before netting successive forehands. A backhand pass gives De Potro the first break point of the set and he converts as Federer hits a backhand long. Could be decisive!

Federer 6-7 6-4 0-1 – The deciding set opens with a successful challenge from Federer and a replayed point. The Swiss then twice hits wide and is unable to get enough on two big serves as Del Potro quickly wraps up the game.

Federer 6-7 6-4 – SET! Federer opens with an ace before Del Potro successfully challenges against another and bludgeons a forehand. Federer responds with a forehand winner of his own but then nets as Del Potro applies pressure at 30-30. A forehand winner gets Federer to set point and he takes it the distance with an ace!

Federer 6-7 5-4 – A big opening serve hurries Federer into hitting long but the Swiss responds with a glorious forehand winner up the line. A good body serve edges Del Potro ahead again and Federer then nets a makeable backhand. The Argentine forces Federer to serve it out with an ace.

Federer 6-7 5-3 – Federer swats away a forehand to get up and running but then pushes one long as he steals into the net. Successive Del Potro errors and another forehand winner and Federer is a game away from levelling matters.

Federer 6-7 4-3 – Del Potro does as Federer in the previous game, racing to 40-0. But Federer gets a point back with an outrageous pushed overhead return and another as he rushes the Argentine into hitting long. He then hits long himself and Del Potro gets back to within a game.

Federer 6-7 4-2 – Federer opens with a fine second serve and follows it with a forehand winner. A cheeky drop shot and long Del Potro forehand and Federer holds to love.

Federer 6-7 3-2 – Federer nets and Del Potro puts away a winner before the Swiss catches the line with a whipped forehand. An overhead wins the game after Federer hits long.

Federer 6-7 3-1 – Federer is unruffled by spectators still taking their seats behind his shoulder and sends down another ace, followed by an unreturnable first serve. He races to 40-0 with a forehand winner before netting a backhand. A blistering forehand winner on the stretch pegs back another point but Del Potro nets to give Federer the game.

Federer 6-7 2-1 – Del Potro stops the rot with a backhand winner but then nets. Federer does likewise and the Argentine smashes an ace up the tee and passes and advancing Federer to win his first game of the set.

Federer 6-7 2-0 – Federer races to 40-0 and wins his eighth straight point to take the game.

Federer 6-7 1-0 – BREAK! Federer opens the second set with a lovely backhand winner and follows with an overhead to apply immediate pressure on the server. A netted backhand give the Swiss three break points and he converts with the first as Del Potro hits long. First break of the match.

Federer 6-7 (7-3) – SET! Del Potro gets the first mini break as Federer hits long then shanks a forehand out to concede another and the Swiss is reeling at 5-1 in the breaker. Another errant forehand and Federer is staring at five set points. He saves the first with an ace and another with a forehand winner but another backhand goes wide as Del Potro has the set.