Good afternoon and welcome to our live coverage of the FA Cup sixth round clash between Manchester United and West Ham United.

Both of these clubs are still fighting for European competition in the league but they can add gloss to their respective seasons with some silverware.

For Man United, the FA Cup represents the only hope of salvaging something from another dismal campaign and is perhaps a last chance for Louis van Gaal to save his job.

West Ham have exceeded all expectations under Slaven Bilic this term and remain very much in contention for a Champions League berth – but they’ll know they have a great opportunity to inflict more misery on their hosts and book a place at Wembley.

Kick-off at Old Trafford is at 4pm and we’ll have all the action as it happens right here.

Let’s get straight to the team news.

Louis van Gaal makes three changes to his side from Thursday’s abject defeat to Liverpool. Michael Carrick, Jesse Lingard and Ander Herrera all come in for Morgan Schneiderlin, Memphis Depay and Juan Mata.

And this is how West Ham will line-up this afternoon.

It’s not like either of these sides needed any more incentive to advance to the last four but news of Arsenal’s elimination, at the hands of Watford, opens the competition up even more.

The Gunners’ freefall continues and now they face the prospect of not their season being virtually over with their backs to the wall against Barcelona in the Champions League too.

Full report from the Emirates Stadium to follow.

As it stands, Crystal Palace, Everton and Watford are the teams in Monday’s semi-final draw. Will it be Man United or West Ham United joining them?

Not long until kick-off at Old Trafford now.

Which way do you see this one going? E-mail ryan@the42.ie, tweet @the42_ie, post a message to our Facebook wall, or leave a comment below.

Paul Scholes, on BT Sport, says it’s a ‘huge week’ in United’s season. Thursday’s disappointing defeat to Liverpool started a pivotal 10 days for Louis van Gaal’s side with the return leg on Thursday and the Manchester derby next weekend.

The atmosphere is building at Old Trafford but there will also be a nervous tension in the air.

Quick check on the teams as the players emerge from the dressing rooms.

Man United: De Gea, Varela, Smalling, Blind, Rojo, Carrick, Fellaini, Rashford, Herrera, Lingard, Martial.

West Ham: Randolph, Antonio, Reid, Ogbonna, Cresswell, Kouyate, Noble (c), Emenike, Lanzini, Payet, Carroll.

Kick-off! Underway at Old Trafford with West Ham, in their changed strip, attacking the Stretford End in this first-half.

Bright start from United. Martial is fouled on halfway but Martin Atkinston plays advantage and Rashford has the chance to run at the West Ham defence.

The young forward squares up Ogbonna but he does well to get the tackle in. The referee goes back and books Winston Reid for that crunching tackle on Martial.

From the resulting corner, meanwhile, Fellaini rises highest but his header isn’t on target.

It’s been a really purposeful start from the hosts. Lingard works it out to the right and he gets on the end of Varela’s cross but his effort is dragged wide.

At the other end, West Ham spring forward for the first time. Cresswell makes good ground down the left and his cross finds Andy Carroll.

He has space and time but snatches at his shot and it’s high and wide.

Chance! The visitors come within inches of taking the lead. Emmanuel Emenike latches onto Carroll’s through ball but he pulls his low shot wide of David de Gear’s upright.

That was so easy for West Ham and another example of United’s vulnerability.

It’s West Ham’s turn to apply the pressure. The ball falls to Payet at the edge of the area but he doesn’t catch it and it trickles through to De Gea. Very likely start to this one.

Another opening for West Ham. Cresswell again provides the attacking outlet down the left and his whipped cross is met by Carroll. On this occasion, he can’t keep his header down but Carroll met that flush on and it was certainly traveling.

Good combination play between Varela, Rashford and Lingard creates the opening for the latter but his effort is tame.

This time it’s Rashford who tries his luck. Varela is given time and space to get his delivery away down this right hand side and it finds the young forward, who tries an acrobatic effort.

It was never really troubling Darren Randolph, however.

Chance! Beautiful move from West Ham and it comes down this left hand side again. Creswell gets to the byline and his cross is perfect for Emenike but he can’t get enough power on it to beat De Gea.

And straight up the other end, United have a sight of goal. Martial shows his pace on the wing to send a deep cross towards Herrera. The Spaniard peels away and strikes a low volley goalwards only for it to deflect off Creswell and wide.

Although the officials don’t think it came off the West Ham defender and it’s actually a goal-kick.

Martial is causing West Ham a lot of problems as he cuts inside off the left wing. On this occasion, he glides past Reid but his shot isn’t powerful enough to get through the bodies and the danger is cleared.

Chance! Lovely move from the hosts but there’s no end product. Rojo charges up field and links well with Rashford. The defender gets the return ball and gets to the byline to pull it back for Herrera.

There are bodies between him and the target but Herrera doesn’t even call Randolph into action as he shoots high and wide.

Martial and Rashford have been extremely lively in the opening half hour. Credit where credit is due, United have played some nice football but have yet to test Randolph.

Fellaini goes into the book for a blatant tug of Mark Noble’s shirt but United are incensed that they didn’t get a free-kick moments earlier.

Noble slid in on Lingard from behind but the referee waved play on and BT’s resident referee, Howard Webb, does in fact confirm that was a foul.

It’s been a frenetic couple of minutes but nothing much to report. It’s all a bit scrappy and neither side have really imposed themselves as of yet.

Rashford is penalised for a foul on Carroll and the set-piece causes United all sorts of problems. There’s a bit of pinball in the box before Carroll’s speculative effort is blocked.

In the day’s Premier League game, there has been a breakthrough right on half-time.

Meanwhile, there will be one minute of added time at Old Trafford.

Half-time! Opportunities for both teams during that first-half but it’s goalless at the break.

It’s been an open and keenly contested game so far. United have conjured some decent football in the first-half but will be disappointed having not tested Darren Randolph.

The visitors will be pleased with their work so far but could easily be in-front at this juncture. Emmanuel Emenike has had two clear-cut chances but shot wide on the first instance and then his header was easily stopped by De Gea.

Martin Rickett Martin Rickett

West Ham get the second-half underway.

And De Gea is called into action straight away. Michail Antonio fires a ball across and the goalkeeper has to dive full-length to get there ahead of the waiting Emenike.

Goals elsewhere.

Period of sustained pressure from United and it results in penalty appeals against Ogbonna. Herrera’s cross is hit into the ground and up onto the defender’s thigh before brushing off the top of his arm.

The referee made the right call on this occasion.

Rashford tries a speculative effort.

AP / Press Association Images AP / Press Association Images / Press Association Images

Promising position now for United. Lingard’s heels are clipped by Payet and the West Ham man goes into the book for that foul.

Blind and Herrera stand over the ball on the edge of the area and it’s the latter who delivers. It’s a perfect ball towards the back post, where Rojo attempts to head back across, only for it to be blocked by Ogbonna.

Varela had to be quick there to snuff out the danger as Emenike looks to gather a ball over the top. A little over 30 minutes to go.

Huge appeals for hand ball as Reid throws himself in front of Herrera’s shot. Brilliant play from United down the left involving Rojo and Martial. Rashford then plays a dummy and it falls to Herrera in space on the edge of the area.

He composes himself and that split second allows Reid to make the block but United were convinced it came off his hand.

Replays such the ball came off Reid’s thigh and then onto his arm so good decision from the officials. That was Reid’s last involvement as Pedro Mba Obiang comes on.

Second change in quick succession from Bilic. Diafra Sakho comes on for Emenike.

Penalty!? Another huge call from Martin Atkinson and this time it’s West Ham who are aggrieved. Payet charges into the box and Rojo comes sliding in and catches the forward but the referee waves away the appeals.

United off the hook there.

GOAL! Man United 0-1 West Ham (Payet)

What a strike! Payet wins a free-kick 35 yards out and he steps up and curls it up and over the wall and past De Gea via the upright.

The 9,000 away fans are in full voice now. That was simply superb from Payet and the moment of magic this match needed.

United looking for an instant reply but Martial is thwarted by Randolph, although the flag was already up.

Michael Carrick then goes into the book for a late challenge. United have 19 minutes to find a way back into this game.

Just sit back and enjoy.

Double change for United. Fellaini and Rashford make way for Schweinsteiger and Memphis.

Final sub from the Hammers as Ener Valencia comes on for Carroll. Old Trafford has gone very, very quiet with just eight minutes remaining.

GOAL! Man United 1-1 West Ham (Martial)

Relief all around Old Trafford! Martial volleys home at the back post after Herrera stands one up.

United in the ascendancy all of a sudden. Memphis gets a run at the Hammers defence but just when he gets the space to shoot, he hesitates and the chance has gone. Five minutes plus injury time away from a replay.

Carrick tries his lick from range and comes within inches of giving United the lead but it was always just curling wide. Darmian, meanwhile, is on for Varela.

The home side pushing for a winner and they’ve come close to settling the tie here. Memphis delivers a corner and it’s bouncing around the box. West Ham are dropping deeper and deeper but eventually get it clear.

Save! Late drama as Antonio forces De Gea into a sprawling save. The full-back hits a daisy-cutter and it looks in until the goalkeeper dives late and gets a strong hand to it.

West Ham are applying all the late pressure as they win their third corner in a row. United just about survive.

Full-time! And that’s it – we’re heading to a replay at Upton Park.

We’ll do it all again under the lights at the Boleyn Ground.

Thanks for joining us and be sure to check The42 throughout the evening for full reaction.