Two-time defending champion Viktor Troicki’s hopes of making open-era history at the Sydney International have ended in a semi-final loss to Luxembourg lefty Gilles Muller.

Troicki was bidding to become the first man to win three consecutive Sydney titles since Australian John Bromwich from 1937-40.

But the Serb suffered an upset defeat against Muller, going down 6-3 7-6 (8-6) on Friday in one hour and 29 minutes.

Muller, who is seeking his maiden ATP title at age 33 and has never progressed beyond the Australian Open fourth round, will meet Britain’s Daniel Evans or Russian Andrey Kuznetsov in Saturday’s final.

Muller, who was so sick last week in Brisbane he struggled to leave his hotel room, enjoyed sweet revenge after being crushed by Troicki in a semi at the 2015 Sydney International.

“It feels great. When I came here, I wasn’t expecting anything because I didn’t play really well in Brisbane and I wasn’t feeling great,” Muller said courtside after the win.

“I was looking to have one or two more matches before the Australian Open.”

The tiebreaker was level at 6-6 when the world No.34 stepped up, winning an absorbing rally then closing out the match with his 16th ace.

“The only thing that is working well at the moment is the serve,” Muller said, having reached the sixth ATP final of his career.

Both players created a single break-point opportunity in a tight first set. Troicki dropped his opening service game, including a double fault, to hand Muller the early advantage.

Muller came under pressure at 5-3 but steadied to serve out the set, including a booming ace that brought up set point.

Troicki’s intensity lifted in the second set but Muller held serve throughout to force the tiebreaker as the temperature hit 37C at Sydney Olympic Park.

Another crucial double fault from Troicki helped Muller take a 5-2 lead in the tiebreaker, but the favourite won the next three points to square the ledger and heighten the tension.