Ghana will play their first World Cup encounter against Italy on Monday before taking on Czech Republic and USA in Group E action.
"There are a lot of teams who will have problems with us," Dujkovic was quoted as saying by FIFAworldcup.com on Sunday.
"We came here to compete and not just to participate, we believe we can do well because we've a very young, competitive and strong team," he added.
Dujkovic guided Ghana to their first ever appearance in the World Cup but question marks have been mounting over their chances in the tournament after bowing out early from the African Cup of Nations in January.
"During the Nations Cup, there was a lot of pressure from the media to sack me, but when we won the next games that changed," the Serbian said. "We are a different team now."