Sunderland were reduced to 10 men late on, before Bukayo Saka converted a stoppage-time penalty to seal Arsenal's fourth win from four.
Arsenal maintained their 100% start to the Premier League season with a 2-0 victory away to Sunderland.
David Raya saved an Enzo Le Fee penalty before Bruno Guimaraes broke the deadlock with a superb long-range strike just minutes later.
Sunderland were reduced to 10 men late on, before Bukayo Saka converted a stoppage-time penalty to seal Arsenal's fourth win from four.

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