The nations begin the campaign they hope will take them to
Serbia may be 11 places ahead of its host in the FIFA world rankings but former international Petric does not believe a draw would be a disaster in its Group A opener, before it faces Wales at home in its own double-header.
He said: "Generally, because it's the first game, so many players have just finished pre-season and started their leagues.
"The first game is so important for every single team. Serbia have a new manager and have some young players who play regularly for our team now.
"It's going to be an important game for us.
"A draw, from my point of view, would be a good score for us if we could take one point from the game but it's going to be very difficult for us."
He added: "Before, we had somebody like Stojkovic or Mijatovic or Stankovic.
"Now we have young players who hope to produce in every single game.
"Maybe the most dangerous player for Scotland might be
"In his last four games, he has scored three goals and is probably in his best form just now."
Scotland is sweating over the fitness of goalkeeper
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Petric says the Scots may be boosted by McGregor's availability if he makes the double-header but does not imagine his presence will make too much difference to Serbia.
He said: "When you play in these situations, especially in these groups, every single team is at the same level.
"It's not important for us who plays just now for Scotland, just as it's not important for Scotland who plays for Serbia.
"It's more important for both teams to keep concentration. The team who keeps better concentration during the game is going to win some points.
"Maybe it is better for Scotland if McGregor is in goal and better for Serbia if he is not in goal.
"At the end of the day, never mind who plays. It's important to have concentration and not make stupid mistakes."
Petric spent a number of years in
He said: "I worked with
"For me, when I worked with him, he was an intelligent coach and he understands football.
"But it's difficult when you play for the national team because teams are at the same level.
"If you make stupid mistakes at this level, you are going to lose the points - but