Third seed Saina took just 33 minutes to beat fifth seed Baun 21-10 21-11 to make the last-four stage where she will be up against an opponent who has beaten her in all their six previous encounters.
Saina, playing her first tournament after becoming the first Indian shuttler to fetch an Olympic medal (a bronze) in London, was hardly troubled in the match on Friday.
With her trademark smashes and better command over the baseline game, the world number four Indian dictated the proceedings and emerged triumphant.
This is Saina's fourth straight win over Baun.
PTI