Matt Barnes -- Trolling Derek Fisher?

Matt Barnes posted this pic on Instagram moments after his nemesis Derek Fisher was fired by the Knicks.So ... this is total shade, right?

Look, it coulda just been bad timing and Barnes just wanted to show off his swag (he is after all a very fashionable guy).

Then again, he hates Fisher's guts and the look on his face says -- "Take that, bitch."

We're going with option #2 ... but hey, choose your own adventure.

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