West Ham's gamble of playing a team full of youngsters and reserve players backfired spectacularly when the Premier League side was thrashed 0-5 by second-tier Nottingham Forest in the third round of the FA Cup yesterday.

Chelsea overcame in-form Championship side Derby County 2-0. Derby has won 10 of its 15 league games since former England manager Steve McClaren took over, but it fell to goals from John Mikel Obi and Oscar as Chelsea set up a fourth-round meeting with Stoke City.

With his squad hit by injury and a League Cup semifinal against Manchester City to come on Wednesday, West Ham manager Sam Allardyce fielded an unrecognizable starting XI that was humbled at The City Ground.

Djamel Abdoun's goal gave Forest a 1-0 lead at halftime before Jamie Paterson scored a hat-trick and Andy Reid completed the humiliation with the fifth in injury time. West Ham's defeat follows Aston Villa's 1-2 loss at home to third-tier Sheffield United on Saturday.

Elsewhere, Tottenham fans pelted Arsenal forward Theo Walcott with coins as their team was overpowered 2-0 in a hotly-contested London derby.

The fierce rivalry turned ugly in the final 10 minutes as Walcott was being carried off on a stretcher.

Despite his knee injury, Walcott taunted the Spurs fans, signaling the 2-0 score with his fingers as he was carried away.

Santi Cazorla swept in the opener in the 31st minute, and the second goal came after a further 31 minutes when Tomas Rosicky charged forward from the halfway line before lifting the ball into the net.

10-man Manchester City was held by Blackburn.

Southampton beat Burley 4-3, Nikica Jelavic scored twice in Everton's 4-0 rout of Queens Park Rangers, and Stoke held on for a 2-1 win over Leicester. Ole Gunnar Solskjaer's reign as Cardiff manager began with a 2-1 win at Newcastle.