I have comprehensively failed to verify this answer. With very little effort, I found websites that described it as a leopard, a puma, a panther and a black panther; but nothing that could by any stretch of the imagination be called reliable. I've searched Slazenger's own website (if that's what it is), and their Facebook page, but failed to find any reference to the logo.
Without meaning to be judgemental, I had to laugh at one forum, which included this contribution from someone in Fareham, Hampshire, dated 2012: "Idiot this morning called it a Puma. That's another brands silly called guess what ... Puma. The Slazenger logo is a panther." Someone came back four hours later with: "I heard the **** with the head full of feathers (can't think of her name) call the animal a slazenger one day!!"
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