By Rob Bishop
Gabby Agbonlahor's first Barclays Premier League goal for a year clinched a crucial win for Villa as Paul Lambert got the better of his former boss Martin O'Neill.
Agbonlahor's superbly-taken 56th minute effort was the first time he had been on target in a league game since scoring against Norwich City on the same weekend last year.
It was certainly a welcome boost for a Villa side who were again beset by problems as they started without the suspended Karim El Ahmadi before Joe Bennett limped off after just 10 minutes.
The visitors survived a strong penalty claim when the ball struck Christian Benteke in the area as Sunderland pressed for an equaliser, but Villa were ultimately good value for three badly-needed points.
It was certainly a memorable day for Ashley Westwood, who made his first start, and for Enda Stevens, who had his first taste of Premier League football.
Although Steven Fletcher had the ball in the net after only four minutes, a linesman had already flagged for offside and it was Villa who created the better early chances.
Matt Lowton was unlucky when he controlled Barry Bannan's deep corner on his chest before unleashing a powerful volley which took a deflection for another flag kick.
Despite losing Bennett with what looked like a knee injury, the visitors continued to knock the ball around confidently, with Eric Lichaj slotting into the left-back role.
Benteke produced a couple of headers, one of which went over while the other was saved by Simon Mignolet.
In between times, a close-range Agbonlahor shot deflected over, but after former Villa man Craig Gardner had fired well off target, the Black Cats enjoyed a sustained spell of pressure which produced some dangerous efforts.
Fit-again Ciaran Clark did well to block a Sessegnon drive following Adam Johnson's fine pass, Lee Cattermole only just cleared the bar with a shot from the edge of the penalty area and Sessegnon headed marginally too high from Seb Larsson's right-wing cross.
Those three chances came in the space of as many minutes, although Villa came close to taking an interval lead when Andreas Weimann moved on to Stephen Ireland's lofted, probing through ball and cut inside his marker for a stinging left-foot drive which was kept out by the diving Mignolet.
The Wearsiders' bright start to the second half saw Gardner's header from a Phil Bardsley cross go for a corner off Bannan while Cattermole headed over after Brad Guzan had only been able to tip away another Bardsley centre.
But it was Villa who broke the deadlock with a goal of immense quality.
A patient build-up culminated with Westwood's precise pass setting up Lowton for a deep cross which Benteke headed down from beyond the far post - and Agbonlahor was perfectly positioned to drill the ball into the roof of the net.
If the striker was relieved at scoring his first league goal for 12 months, though, it was also a painful experience.
He was caught by Carlos Cuellar's desperate challenge and needed treatment before he could continue.
Stevens, who had just replaced Lichaj, also needed attention after a collision with Louis Saha as the Sunderland sub headed just over from Larsson's free-kick, but in the 76th minute there was nearly a second Villa goal.
Weimann, Lowton and Ireland combined superbly for the Austrian to hit a fierce drive which Mignolet did well to parry.
It took a late save by Guzan from Cattermole to keep the lead intact , but Villa's travelling band of supporters were in buoyant mood as the final whistle sounded.
Sunderland: Mignolet; Bardsley (Campbell, 81), O'Shea, Cuellar, Colback; Larsson, Cattermole, Gardner (McClean, 67), Johnson; Sessegnon (Saha, 67), Fletcher. Unused subs: Westwood, Rose, Kilgallon, Vaughan.
Villa: Guzan; Lowton, Vlaar, Clark, Bennett (Lichaj, 11, Stevens 71); Westwood, Bannan; Weimann (Holman, 85), Ireland, Agbonlahor; Benteke. Unused subs: Given, Albrighton, Delph, Bowery.
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