It is the seemingly benign garden game which – as all children secretly understand – actually offers unrivalled opportunities to legitimately smash a tennis ball straight at underprepared sibling.
Now, while there is certainly no suggestion it was deliberate, a colleague has taken the chance to do just that while playing Swingball with Nicola Sturgeon.
But the party leader – well known for dishing out blows to opponents in both Holyrood and Westminster – was perhaps not expecting the ferocious head-height serve offered up by her fellow member.
Video shows the ball crashing straight into Ms Sturgeon’s head, before she apparently throws in the towel.
“Outrageous,” someone in the crowd can be heard saying in footage of the incident. “Outrageous.”
But Ms Sturgeon proved she could roll with the blow following the incident on Saturday afternoon.
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“Great time in Dennistoun today – until the moment @AnneMcLaughlin whacked me on the head with a tennis ball,” she later tweeted.
“I play to win these days,” replied Ms McLaughlin. “And I did.”