The 29-year-old had made a total of 12 appearances for the Gunners this season, and had attracted growing criticism from supporters.
He'd been pretty suspect early on in the season, but it was the fateful game at Old Trafford where he came up against an in-form Antonio Valencia which had appeared to be one of his worst showings.
But in 2013 he stepped it up a notch, or down a notch dependent on your perspective, with a shocking performance against Brighton in the FA Cup - which led to Piers Morgan decrying him as Arsenal's worst ever player, and an even more damaging one against Liverpool when he came on as substitute.
He was that bad, that he convinced Arsene Wenger to immediately go and spend £8 million on a new left-back and ship him off to Brazil for the rest of the season.
It appears abundantly clear, that while Santos had a few good moments in his debut season; a goal against Chelsea in the 5-3 win at Stamford Bridge, and a last day strike against West Brom in a 3-2 win which earned them Champions League qualification, that he will be remembered for the bad times, and the nervousness he brought to supporters whenever he was on the pitch.
He will be remembered as the defender who helped make Liverpool's Jordan Henderson look like Lionel Messi when he skipped past him and held him off to score against them last month.
You can watch the goal again below...
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image: © wonker