This was no swashbuckling display from Liverpool, but in the end the visitors had enough chances to put the game beyond doubt long before Andriy Voronin's 87th minute strike.
Voronin, in fact, was guilty of wasting a number of very good chances before his late goal sealed the win.
Sunderland had been given fair warning as to the threat the Liverpool forward posed.
Just 30 seconds into the game, Greg Halford made a hash of his back pass to let in the Ukrainian, but Sunderland goalkeeper Craig Gordon stood up well and did enough to deflect the shot wide.
The big Scot was in fine form in the Black Cats goal but, despite a number of telling saves, he was unable to keep the visitors at bay for the full 90 minutes.
Liverpool threatened several times during early exchanges but were never able to get a clear strike at goal.
Sunderland though didn't let the visitors have it all their own way but were restricted to ten minutes in the opening half where they could say they were on top.
Daryl Murphy had a half-chance to give his side the lead when Michael Chopra nodded the ball down into his path, but the Irishman fired high into the crowd from about 25 yards out.
Sunderland were restricted throughout the clash and Liverpool's defence seemed comfortable with everything Roy Keane's men could throw at them.
With the half drawing to a close it seemed as though the Reds would rue their missed opportunities, but a thunderbolt from Momo Sissoko gave them a deserved lead on 37 minutes.
It was the midfielder's first goal for the club and the Reds' 7,000th in top-flight league football.
After the break, Liverpool and Sunderland both started brightly, but again it was the visitors who were to have the better chances.
Gordon in the home goal made a number of key saves as both Fernando Torres and Voronin should have done better.
But the latter was to have the final say as he finished off any slim hopes Sunderland had of getting back into the game.
The Liverpool frontman fired a low, hard shot across goal and under Gordon to make it 2-0 in the dying stages.
It was no less than Liverpool deserved and should ensure that, if they didn't know it already, Sunderland are now well aware of how tough life in the top-flight can be.