Decreased salivary immunoglobulin A (sIgA), a component of mucosal immunity, is associated with intensive physical activity: suggesting that sIgA may be used for the monitoring of mucosal immunity with footballers. We investigated changes in sIgA in elite footballers, in response to training and match-play. There was a decrease in sIgA following training, with a return to pre-training levels after 18 hours of rest. This return to resting levels was not observed following competitive match-play. Overnight rest was sufficient for mucosal IgA recovery following training but not following two successive matches, suggesting that sIgA may be used to monitor training in multi-sprint sports.