World No.79 Rhustavito defeated No.93 Jayaram 21-14, 21-10 in 28 minutes to win the title at the Nguyen Du Cultural Sports Club.
Ajay Jayaram saw off seventh seed Igarashi 21-14 21-19 in a 34-minute match.
Kidambi Srikanth jumped four places with 66,923 points to occupy fourth place behind China's Lin Dan.
Kidambi Srikanth, who lost in the quarterfinals in Japan Open, remains the highest-ranked Indian male player at eighth.
Twelve Indian male badminton players are currently ranked in the top 100, with seven in the top 50.
Olympic medallists PV Sindhu and Saina Nehwal will play in the World Championships in Glasgow, beginning August 21.
India start mixed team tournament on disappointing note, lose 1-4 to Denmark.
Ajay Jayaram, unseeded in the tournament, produced a remarkable comeback against Viktor Axelsen after being completely outclassed in the first game.
Saina Nehwal needed 40 minutes to get past Indonesia's Fitriani and book her place in the semifinals of the Malasyaia Masters
Top seed Saina Nehwal, who is desperately looking for a win to boost her confidence after recovering from a knee surgery which derailed her Rio Olympics campaign lat year, spanked Thailand's Chasinee Korepap 21-9 21-8 in a lop-sided contest.
Chennai Smashers claimed the Premier Badminton League 2017 title on Saturday after edging out Mumbai Rockets 4-3 in a thrilling final
PV Sindhu-led Chennai Smashers defeated Mumbai Rockets 4-3 to lift the 2017 Premier Badminton League 2017 title in New Delhi on Saturday. Catch all the highlights of PBL 2017 here.
Mumbai Rockets defeated Hyderabad Hunters 2-1 in a PBL 2017 clash in Mumbai on Wednesday. Catch highlights of the PBL 2017 match here.