Holders Manchester United were shocked by West Ham at Upton Park as the Hammers cruised to the semi-finals with a 4-0 victory against United in the quarter-finals of the English League Cup a.k.a. The Carling Cup.

Former United striker Jonathan Spector was in a confident mood as he scored a brace, first with a header and then with a close range tap in, to send West Ham into the break with a 2-0 lead.

Ferguson brought striker Fredrico Macheda on for Bebe at half-time, but it was the Hammers who did the attacking. Carlton Cole scored twice within 10 minutes to kill the game and send United crashing out of the cup.

Nigerian striker Victor Obinna put up an impressive show and had a hand in all of four goals as the Hammers continue their revival with two wins in two games in all competitions.

United did field a weakened team for the match, but they still boasted the likes of Ryan Giggs, Darren Fletcher and Javier Hernandez. On the other hand, West Ham, who are bottom of the Premiership, was full of promise and their boss Avram Grant insisted after the victory that his team's bad patch was finally over.

He said, We've been playing well for two months, apart from our defeat at Liverpool. I was sure if we continued to do that we would be fine, though I didn't expect the nature of this win. We always play the same, but just created a few more chances and were more clinical. We want to be in the final, of course.

It's a very important season for West Ham. We have bought new players and are trying a different formation of football. You have to do things step-by-step.

United manager, Sir Alex Ferguson, was at a loss for words as he admitted he couldn't explain his side's abysmal defending.

He said, I didn't expect that, that's for sure. If you analyse it the goals we gave away were absolutely too soft. We didn't expect that, they were terrible goals for us. You can't just give goals away at this level. That first goal was a break for them. We were in control in the early part, played some good football. But goals change games.

Meanwhile, Arsenal cruised into the semis with a 2-0 victory over a disappointing Wigan.

It was Arsenal who did all the attacking, but it was an own-goal by Antolin Alcaraz which opened the scoring. Midway through the second half, Nicholas Bendtner tapped in from a close range to make it 2-0. Bendtner and Vela were guilty of missing further chances, as late substitute Samir Nasri also had a shot cleared off the line.

Arsenal barely moved from second gear and yet could have scored much more had their finishing been more cynical.

West Ham and Arsenal will find out who their opponents are in the semis after Wednesdays ties between Birmingham - Aston Villa and Ipswich - West Brom.