Blackburn forced a replay against Manchester City in the third round of the FA Cup in one of many upsets over the course of the weekend. REUTERS

The magic of the FA Cup was well and truly alive in the third round over the course of the weekend with Arsenal and Tottenham dueling while the likes of Rochdale, Nottingham Forest and Sheffield United caused upsets to make for an interesting progression in the competition.

The Gunners faced their bitter rivals in what was seen as the game of the round, and came out on top thanks to goals from Santi Cazorla and Tomas Rosicky. Arsene Wenger's men looked the dominant side across the 90 minutes and are now a step closer to breaking an almost-decade long trophyless spell.

Some controversy occured as Theo Walcott was stretchered off with the winger signalling the scoreline to Tottenham fans who were reportedly throwing coins and other objects in his direction.

Theo Walcott
Theo Walcott signals the scoreline to Tottenham fans as the Arsenal winger is stretchered off at the Emirates. REUTERS

Blackburn caused somewhat of an upset early on in the fixtures, forcing a replay against Manchester City after Scott Dann cancelled out Alvaro Negerdo's goal in the 55th minute to force the final score to 1-1.

Aston Villa were equally shocked on the back of comments from manager Paul Lambert that he could do without the domestic competition as his side fight for safety in the Premier League, losing 2-1 to Sheffield United and leaving fans dismayed as they exited the competition.

Rochdale were also successful in pulling off an upset, defeating Cup contenders Leeds 2-0 in a convincing display that included goals from Scott Hogan and Ian Henderson.

In Sunday's action Chelsea took a somewhat expected 2-0 win over Championship side Derby, though the Rams put up a good fight in the first half in particular. Goals from John Mikel Obi and Oscar proved too much for the side though and the Blues will now face Stoke in the next round.

John Mikel Obi
John Mikel Obi celebrates his goal against Derby.

In perhaps the biggest surprise result of the round Nottingham Forest put five goals past West Ham to thrash the Premier League side and earn their place in the latter stages of the FA Cup, with Sam Allardyce now under even more pressure as his squad sit in the relegation zone.

Allardyce admitted after the match there could be repercussions for the result, telling reporters: "There might be, who knows? It's their decision, not mine.

"I'm not saying it won't happen unless I start to get results. I have got to get results, I know that.

"But I made them (Gold and Sullivan) aware of what would happen today because I'm not in the position to go and do these things without telling everybody internally what is planned for the next few games."

Liverpool were in action against Oldham and the side breezed past their lower-league opposition thanks to a goal from Iago Aspas - his first for the Reds since moving to the club in the summer - and an own goal by James Tarkowski.

Manchester United v Swansea
Manchester United went down to Swansea in their FA Cup match-up.