Arsenal can close Manchester United's lead to one point with victory over Stoke City tomorrow.
An opportunity, Alex Song feels, Arsenal simply cannot afford to spurn.
"It is not good to have another match [the replay] but I am 100 per cent sure we will win the game at Emirates," Song told arsenal.com.
"We managed the game well apart from the last ten or 15 minutes. But we need to leave this game because we have an important match on Wednesday. The win is very important for the League.
"It is important just to take the next step. If we win this game we are a point behind Manchester United.
"We are working hard because this year is very important. Everybody has waited for this moment."
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