Newcastle edged into the Uefa Cup knockout stages despite missing a host of chances at St James' Park.
Duff was a constant menace down the Newcastle right wing
The hosts were rarely threatened by Ventspils and Damien Duff squandered four opportunities in a tie that was completely dominated by the Magpies.
Emre and Charles N'Zogbia had long-range shots comfortably saved and James Milner had a 30-yard free-kick that hit the Latvians' crossbar.
Despite failing to find a winner, Newcastle progress 1-0 on aggregate.
Before kick-off, the Magpies paraded new £10m signing Obafemi Martins on the pitch to rapturous applause from the Newcastle faithful.
And the new signing from Inter Milan will be relishing turning out in the black and white stripes if Duff, N'Zogbia and Scott Parker can create as many chances as they did against the Latvians.
The unusual sight of empty seats inside St James' Park suggested that the Newcastle fans expected a smooth progression to the Uefa Cup.
And the hosts completely bossed the tie without ever looking like conceding.
Glenn Roeder's side were patient in their build-up and peppered Andris Vanins' goal with long-range efforts from Emre, James Milner and Duff.
Irishman Duff spurned three other decent efforts in the first half, while Celestine Babayaro and N'Zogbia both tried their luck down the left with two half-chances.
Duff exposed the Ventspils defence on numerous occasions and highlighted the gulf in quality between the two sides.
Titus Bramble saw his lob from the edge of the area drift just over in the second half, while Emre again hit the target with a long-range drive.
But the 2,500th competitive fixture at St James' Park ended without a goal meaning Newcastle are in Friday's draw for the next round.
Newcastle manager Glenn Roeder:
"I'm very pleased with the performance but I would have liked one of the opportunities to go in - that would have made us more relaxed in defence.
"The boys did everything that we asked of them. They put in a good stint and moved the ball from the back to the front very quickly.
"But they just got everything in the way and they defended well."
Newcastle: Harper, Carr, Taylor, Bramble, Babayaro, Duff, Parker, Emre, N'Zogbia, Luque, Milner.
Subs Not Used: Krul, Solano, Butt, Ramage, Huntington, Pattison, O'Brien.
FK Ventspils: Vanins, Kacanovs, Ndjoumek-Ndeki, Gorkss, Pokarynin, Vukovic, Dubensky, Bicka, Zizilevs, Rimkus (Stukalinas 90), Kolefnicenko (Kosmacovs 86).
Subs Not Used: Davidovs, Soleicuks, Sokolskis, Goncars, Lazdins.
Ref: Thomas Einwaller (Austria).