The New Zealander won 11-9, 11-9, 9-11, 11-9.
After coming through two five-game encounters earlier, the third seed Indian still looked fresh for another battle.
Only once has Joshna beaten Joelle earlier in their eight meetings and that too seven years ago. Much has happened since. Joelle is 9th in the world, four rungs above Joshna but it proved a lively match with points going neck and neck. In fact the Indian had led 9-8 in the first game where Joelle came up with three winning drives.
In the third game, Joshna earned two 'strokes' in the end stages and that sought of put a check on the rival. But the one game reverse did not unsettle Joelle who like in the earlier games, showed the superiority in the end stages with crisp volleys and drops to stop the Indian.
"That was really tough," said the champion at the end of the 45 minute tussle.