Kammala jumla mai zuwa: Petrosian ya sami lambar babban mashahurinsa ta hanyar cin kwallaye a gasar cin kofin duniya na 'yan kasa da shekaru 18 a 2002, Batumi Open a 2003, da Aeroflot Open a Moscow a 2004. A wannan shekarar ya yi daidai da na 2 da na 3 tare da Zhao Jun a Gasar Cin Kofin Duniya ta Junior a Kochi, Indiya. A shekara ta 2005, ya yi daidai da na farko a Tehran, Kish da Lausanne; a shekara ta 2006 ya yi daidai da na farko a Lyon da Dubai; a shekara ta 2008 ya yi daidai da na farko a Wheeling, Illinois da Las Vegas. A cikin wannan shekarar ya lashe lambar zinare ta tawagar (tare da Levon Aronian, Vladimir Akopian, Gabriel Sargissian da Artashes Minasian) a gasar Olympics ta duniya.
Gasar Olympics ta Chess ta 38 a Dresden. A shekara ta 2011, Petrosian ya yi daidai da 1st <unk> 3rd tare da Marat Dzhumaev da Anton Filippov a cikin Georgy Agzamov Memorial a Tashkent kuma ya lashe gasar a kan tashin hankali. A wannan shekarar ne ya lashe Gasar Chess960 ta Armeniya ta farko, ya yi daidai da 2nd <unk> 4th tare da Abhijeet Gupta da Magesh Panchanathan a gasar cin kofin Chess ta Orissa International GM Open ta uku kuma ya zo na farko a 31st Villa de Benasque Open. A watan Janairun 2012 Petrosian ya lashe Gasar Chess ta Armeniya kuma a watan Fabrairun 2012 ya zo na farko a Gasar Rapid ta Armeniya. A watan Janairun 2013 ya lashe gasar zakarun Armeniya a karo na biyu. Ya kuma lashe kyautar farko a cikin International "Grand Europe Open Albena-2013" a Bulgaria. A cikin 2017 ya gama na farko a cikin 45th Annual World Open a Philadelphia.