Mikel Arteta jumped to Willian's defence after Piers Morgan slammed the winger following Arsenal's FA Cup win over Newcastle.
But the Gunners boss also warned his player that it's time to start producing the goods after he struggled in the 2-0 victory.
Arteta reverted to a more experienced attack for Saturday's third-round clash, with Arsenal's young guns having earned three Premier League wins in a row.
But Willian and fellow winger Nicolas Pepe failed to hit their stride and missed decent chances, and were both eventually hooked.
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