Marussia's hopes of competing in Formula One this season appear to have been dashed after Bernie Ecclestone revealed their request to race with last year's car had been voted down.

The team wanted to race with last year's model before building up their resources to make a more credible challenge in 2016.

"It needed all the teams to agree and there were three or four of them that didn't agree," F1 chief Bernie Ecclestone told the Independent, external.

Your chance to get involved.

It is going to be a hell of a weekend for rivalries, beginning with Wales v England in the Six Nations (125 meetings, 56 wins to Wales, 57 to England, with 12 draws), followed by two big Premier League derbies in North London and Merseyside tomorrow.

So we want you to tell us your favourite all-time sporting rivalry.

Image source, Getty Images

Is it Muhammad Ali and Joe Frazier, Bjorn Borg and John McEnroe, or maybe - and granted this an ever-so-slightly personal choice - Bury v Bolton in the late 80s?

Let us know now at #greatrivalries or at the BBC Sport Facebook page, external.

More bad news for Tiger Woods overnight, with the former world number one forced to withdraw from his latest comeback tournament - the Farmers Insurance Open at Torrey Pines - because of back problems.

The 14-time major champion was two over par when he abandoned his first round after 11 holes.

Image source, Getty Images

The 39-year-old American spoke to his playing partners before walking off the course and into a waiting car.

His early departure comes after he shot a career-worst 82 in the second round at Phoenix last week.

And, just so you know what's in store this weekend in the Premier League, here's the fixture list - including two mouth-watering derbies in London and Merseyside...

Saturday: Tottenham v Arsenal (12:45 GMT), Aston Villa v Chelsea, Leicester v Crystal Palace, Man City v Hull, QPR v Southampton, Swansea v Sunderland (all 15:00); Everton v Liverpool (17:30).

Sunday: Burnley v West Brom (12:00 GMT), Newcastle v Stoke (14:05), West Ham v Man United (16:15).

Cornelius Lysaght
BBC horse racing correspondent

Today's jump racing fixtures at Bangor on Dee and Kempton are both subject to second inspections at 10.00, but Newcastle goes ahead as planned.

We know you're a busy lot who like to plan their day, so here's a run-down of all those Premier League news conferences taking place today - starting with Steve Bruce, if he's on time, in four minutes...

Hull 08:30 GMT, Arsenal 09:00, West Ham 09:30, QPR 09:45.

West Brom 11:30 GMT (new signing Darren Fletcher) 13:00 (Tony Pulis); Man City 12:45

Image source, Getty Images

Newcastle 13:00 GMT, Swansea 14:00, Stoke 14:30, Burnley 14:30

Chelsea 14:30 GMT (hopefully with Jose, if he shows), Man United 15:30

As promised, we'll bring you what's said.

BBC World Service reporter Nick Cavell was at the Africa Cup of Nations semi-final game and described what happened: "The trouble began before half-time, with fans angry at some refereeing decisions.

"Bottles were thrown onto the pitch and the Ghana players were forced to leave the pitch at half-time under a tunnel made of riot shields. The bottle throwing continued after the break.

Image source, Getty Images

"A police helicopter tried to intimidate fans by flying just 20 or 30 metres above their heads. Then police moved in with tear gas and batons to move the fans away. The press box emptied, too, as the tear gas spread."

BBC World Service reporter Steve Crossman, who was forced to stop commentating and run for cover, added: "You could see fans hanging off the stadium walls as they tried to get to safety. All in all, nobody comes out of this in any good shape at all."

Cornelius Lysaght
BBC horse racing correspondent

As well as Kempton and Newcastle, Bangor on Dee to hold 8am inspection now as well.

When Ghana and hosts Equatorial Guinea met in the Afcon semi's last night it turned into what was described by one official as "a war zone".

Image source, Reuters

Play was suspended for more than 30 minutes because of crowd trouble as players ducked bottles thrown from the stands, Ghana fans sought safety behind a goal, riot police used tear gas and a helicopter hovered over the stadium.

"It's like a war zone," the Ghana Football Association (GFA) tweeted, claiming "barbaric acts of vandalism" and "unprovoked violent attacks" had taken place inside the stadium.

Image source, Getty Images

Amazingly the game was completed, with Ghana winning 3-0 and setting up a Sunday final against Ivory Coast.

As well as all the Premier League action, we'll also bring you all the breaking sports news throughout the day and build-up to tonight's Six Nations opener between Wales and England at the Millennium Stadium.

We'll also have Tiger Woods' latest news and a look at the opening round of Super League games. Busy day, eh?

Let's begin, though, with a look at what turned out to be an incredible semi-final at the Africa Cup of Nations, incredible for all the wrong reasons...

Morning. So, will we get to see this today.

Image source, Getty Images

Or will it be this?

Image source, Getty Images

After missing his last two dates with the media, Chelsea boss Jose Mourinho is due to give a press conference at 14:30 today. But will he turn up?

He is one of 12 - that's right, 12 - Premier League managers talking today, before the weekend's top-flight action. We'll bring you the best of everything they say.