Jermain Defoe's 70th minute penalty, contentiously awarded but despatched with ease, condemned Sunderland to yet another away defeat and kept Portsmouth on course for Europe.

Defoe, a £7.5 million capture from Tottenham, scored on his debut against Chelsea three weeks ago and had the home fans toasting his name again with an unstoppable finish after referee Phil Dowd decided Niko Kranjcar's fall over Phil Bardsley's foot constituted a spot-kick.

It meant a 10th successive Barclays Premier League away defeat for Sunderland - an unwanted club record.

As well as being luckless on the penalty incident, they had one or two earlier opportunities to produce a shock result.

For Portsmouth, victory was another step along the road they hope will lead to at least a UEFA Cup berth next season.

Although Dickson Etuhu could easily have added to his first Sunderland goal two weeks ago in the opening minutes, a poor first half was notable only for a series of spectacular collisions.

With a touch of anticipation, Etuhu, who scored in the 2-0 win over Wigan, would have headed in a second-minute free-kick by the returning Grant Leadbitter which caught Pompey sleeping.

But soon afterwards, team-mate Phil Bardsley had to go off for treatment after colliding with keeper Craig Gordon in his own area.

Later, a crashing three-way collision in midfield between Kranjcar, Papa Bouba Diop and Sunderland skipper Dean Whitehead amazingly produced no serious casualties.

Neither England's David James - playing his 501st Premier League game - nor Scotland's Gordon were seriously troubled for the reminder of the first half which turned into a heavily-populated midfield battle of attrition.

Defoe badly scuffed a chance wide for Pompey after a good ball in by Glen Johnson and was probably relieved to see an offside flag waving.

Then Sulley Muntari, having made a mess of one free-kick, fired another from 25 yards just over the top.

Darryl Murphy's shot was blocked by Sol Campbell and although there were the odd optimistic shouts for handball, referee Phil Dowd was not interested.

Hermann Hreidarsson also headed wide but the first half was summed up by a yellow card for Pompey's Johnson who simply refused to stop arguing with the referee after being pulled up for a foul.

Coach Joe Jordan also seemed to get involved with the fourth official and was sent from the technical area by Dowd.

Defoe finally tested Gordon with a leaping half-volley to connect with Muntari's cross after the Ghanaian had stormed down the right in the 51st minute.

But with little further sign of a breakthrough, Pompey boss Redknapp put Kanu on just after the hour in place of the ineffective Milan Baros.

Johnson, despite his first half tantrum, was a lively force for Pompey and his low shot had Gordon diving again.

Sunderland looked set to save a point but just when Pompey looked like running out of ideas, Kranjcar cut in from the left on his right foot and fell over the luckless Bardsley's outstretched boot.

Dowd, perfectly placed, pointed emphatically to the spot.

Defoe made no bones about stepping up to score his second goal in successive home games, drilling in from the spot with Gordon diving the wrong way.

Defoe could have added two more before the end, going close with right-foot shots, one of which he claimed hit a hand.

And Sunderland's discipline deteriorated, with Danny Collins and substitute Dwight Yorke both booked for fouls on the marauding Johnson.

Teams:

Portsmouth James, Johnson, Campbell, Distin, Hreidarsson, Diop, Diarra, Muntari, Kranjcar, Baros (Kanu 64), Defoe.

Subs Not Used: Ashdown, Lauren, Utaka, Davis.

Booked: Johnson.

Goals: Defoe 69 pen.

Sunderland Gordon, Bardsley, Nosworthy, Evans, Collins, Whitehead, Leadbitter (Yorke 79), Etuhu, Murphy (Prica 84),Reid (Chopra 70), Jones.

Subs Not Used: Ward, McShane.

Booked: Collins, Yorke.

Att: 20,139

Ref: Phil Dowd (Staffordshire).