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Theo Walcott scored another crucial goal against Chelsea.
Theo Walcott's performance at Stamford Bridge typified his excellent season. He was quiet for long periods in the first half, frustratingly offside on more than one occasion, and on the periphery of Arsenal's passing game.
Then he timed one run to perfection and finished confidently past Petr Cech. That is what he can do: it only takes a second.
Joey O'Brien, West Ham's de facto left-back, will be all too aware of that searing pace. He will know he has no chance of winning a straight race with Walcott, so will have to use every trick in the defender's proverbial book to contain him.
Walcott, on the other hand, will be looking to use his extraordinary physical gifts to exploit a possible weak point in the West Ham back line.
What do you think? Where will this game be lost and won? Let us know below.