Troicki was banned for 18 months in July last year for violating the International Tennis Federation's (ITF) anti-doping laws after failing to supply a blood sample at the 2013 Monte Carlo Masters, with the ITF refusing to accept his justification of illness for not giving blood.
The sentence was cut to 12 months by the Court of Arbitration for Sport (CAS), but his long absence has meant that the Serbian has plummeted to number 842 in the ATP world rankings.
However, the former world number 12 will now have the chance to make a significant movement up the rankings in Gstaad after being handed the third and final wild-card entry into the ATP 250 tournament.
But the 28-year-old will require a strong performance if he is to have any chance of making the latter stages of the competition.
A high quality field is headed by defending champion Mikhail Youzhny, who will be looking to become the first man since Sergi Bruguera in 1994 to retain the title.
Youznhy beat Robin Haase in straight sets on the clay to secure a 10th ATP title but, although he added an 11th success at the Valencia 500 last October, Youzhny has struggled for form in 2014.
The Russian has not gone past the last 64 of any grand slam so far this year, and heads into the tournament having lost in the second round of the Hamburg Open to 17-year-old Alexander Zverev.
Haase's prospects of going one better than last year look slim following the Dutchman's defeat to Zverev, who hammered the world number 51 6-0 6-2 in the first round in Hamburg.
Perhaps unsurprisingly there is a heavy Spanish presence for the clay-court tournament.
The Iberian challenge is headed by 2011 winner Marcel Granollers, while Fernando Verdasco – runner-up to his compatriot three years ago – and Guillermo Garcia Lopez will also be hoping to make an impression.