BELGRADE Oct 8 Austria forward Marko Arnautovic poses the greatest threat to Serbia's hopes of keeping their 2018 World Cup qualifying campaign on track, captain Branislav Ivanovic said on Saturday.
The sides clash in Group D at Red Star Belgrade's stadium on Sunday and Chelsea defender Ivanovic said the outcome could have a telling impact on Serbia's bid to reach their first major tournament since the 2010 World Cup.
Having played against Arnautovic several times in the Premier League, the 32-year-old right back heaped praise on the Stoke City forward, who was born to a Serbian father and an Austrian mother.
"I have the utmost respect for Arnautovic because he has matured in the last year and a half or two," Ivanovic told a news conference.
"He has drawn a lot of attention here because of his heritage and in footballing terms, he has perhaps improved beyond the quality of the club he plays for," he added.
"We have to close him down and if we do, we have a good chance of keeping a clean sheet."
Wales, Serbia, Austria and Ireland each have four points from two games in what is shaping up to be a fiercely competitive section, with only the group winners guaranteed an automatic berth in the 32-team tournament in Russia.
Georgia and Moldova are yet to earn a point.
Serbia enjoyed a 3-0 win at Moldova on Thursday while Austria were held to a 2-2 home draw by Wales.
"The match against Austria is incredibly important for both teams, not just for the sake of taking three points but also for the entire qualification process," Ivanovic said.
"In the past few campaigns, we were pretty much out of contention after the opening two or three games whereas the situation is entirely different now.
"It could be a turning-point for either team and winning would represent a giant step towards the World Cup." (Editing by Ed Osmond)