Drink pickle juice during a match?? I'd be reluctant to do it. A well known phenomenon in physiology is shunting, whereby the larger part of your blood circulation is directed where needed. During physical activity, it's directed away from the GI tract and towards skeletal muscle doing all the work. Conversely, when eating and digesting, blood is directed away from skeletal muscle towards the GI tract to facilitate absorption of nutrients (thus the advice not to go swimming right after eating.) It's been demonstrated that a circulation-deprived stomach and intestine is less protected from ingested acid, such as the acetic acid that is vinegar, or even the acid the stomach itself produces, and more at risk for development of an ulcer.