A goalless draw in the first leg of their play-off tie in Denmark leaves Martin O'Neill's side 90 minutes away from taking their place in Russia, with the second leg scheduled to take place on Tuesday [14 November] in Dublin in a virtual winner-take-all contest.
Dunne, who won 80 international caps with Ireland, was thrilled with Duffy's display in Copenhagen and feels it is only a matter of time before Arsenal and Liverpool – both of whom are lacking in physically dominating defenders - take note.
"His tackling is outstanding," Dunne told Newstalk, according to Sport Review. "His reading of the game is improving. There's no-one better when it comes to heading the ball in the air. His performances for Ireland and Brighton over the last two months, he is putting himself in the bracket where people are starting to notice him now.
"When you think of Liverpool and Arsenal are desperate for a centre-half, he is someone people are going to start talking about. Brighton are keeping clean sheets and in the top 10 in the league. He's one of their star performers. He is young enough to go to that level. He has so much room to grow."
Duffy has played a key role in Brighton enjoying an encouraging start to their first top flight campaign for 34 years, with four clean sheets in 11 games helping the club occupy eighth position in the Premier League table.
The Seagulls have a better defensive record than both Arsenal and Liverpool, with only five sides having conceded fewer than the 11 shipped by the south coast club during the opening four months of the campaign.
Both Arsenal and Liverpool have been advised to add to their defence in the January transfer window having let in 16 and 17 goals respectively in the league this season, though it remains to be seen whether Duffy will be among those targets.
"They work hard at their positioning, they are not afraid to put their bodies [in] there," the Brighton boss said after the 3-0 win over West Ham United, according to RTE. "They probably get more blocks in than anybody else in the side.
"We're benefiting from the amount of games they've played together and the relationship they have. Shane is aggressive in the air, that's a little bit of a dying art. Between the two of them they cover a lot of the qualities you want from a centre-half."