The longest marathon playing tennis was 30 hr 30 min 30 sec and was achieved by Christian Albrecht Barschel and Hauke Daene (both Germany), at Molln Tennis Club, Molln, Germany, on 11-12 July 2008.

The pair raised over EUR 5,000 for a German brain tumour care organisation.

The pair completed 39 sets and were in their 40th set when the marathon ended.

The score was 21 sets to 18 in favour of Hauke Daene.