The Australian centre-half and the former China international have formed a strong partnership in the centre of defence for Chinese Super League club Shaanxi Chanba and Djulbic has breathed a sigh of relief that he doesn't have to play against the 33-year old hardman.
"To be honest, he's a very physical player and sometimes when I see him tackle I go, 'Oh my God, I don't want to be playing against him'", Djulbic told au.fourfourtwo.com.
"Sun is one of the most respected players in the Chinese league with over 100 caps for China... not many Chinese players have been in the EPL, so he's very well respected. Everyone loves him.
"The combination has been working well so far and I'm really enjoying it. We haven't conceded a goal yet. He speaks English well too which helps."
Djulbic and Sun have helped Shaanxi to two clean sheets from their opening two CSL matches this season and take on 13th-placed Henan Jianye at home this weekend.