Steve Stone has told Pompey fans to get off Yakubu's back.

Winger Stone started his first game for a month and won the penalty that gave Yakubu the chance to notch his 14th goal of the season.

But Yakubu, 22, was otherwise quiet and the Fratton Park crowd grew increasingly frustrated with the club's biggest asset, who Stone insists is still affected by last month's transfer window speculation.

Yakubu, who is rated at £10m by Pompey, was linked with Newcastle United, Liverpool and Chelsea throughout January and is expected to leave for a bigger club at the end of the season.

But he is not showing the form that earned him a reputation as one of the Premiership's top strikers at the end of last season and the beginning of this - and Stone believes he needs to be encouraged.

He said: "Yak gets called lazy and the crowd get on his back sometimes, but he has never been any different. He plays the same every week, whether he's scoring goals or not.

"But he's been affected by the speculation. He's a young kid who's come to this country and people are saying he's worth a lot of money.

"It's very difficult for a seasoned pro not to be affected by all the speculation and I feel for the lad.

"He must have wondered what was going on with other players leaving and people are still talking about him going. It must be really hard not knowing what's happening with his situation

"I thought he played fantastic against Middlesbrough after the transfer window closed. He looked back to his old self, but we'll just have to wind him up in training and tell him to get his head down."

Pompey created several chances in the first half after Arjan De Zeeuw had turned home Luke Moore's left-flank cross at the near post to give Aston Villa a 17th minute lead.

Patrik Berger and Yakubu both struck the woodwork, a 25-yard drive that struck the inside of the left post, and a header that bounced off the opposite upright, either side of the 23rd-minute equaliser.

Stone was felled in the penalty area by Gareth Barry and Yakubu, who had been told to show an improvement on the eve of the game by boss Velimir Zajec, sent Thomas Sorensen the wrong way.

But it was Villa who dominated the second half and Juan Pablo Angel struck Konstantinos Chalkias's crossbar with a bullet header from a pinpoint Nolberto Solano centre.

Then German international Thomas Hitzlsperger silenced most of the 20,160 crowd with a thunderous 25-yard volley, after the Pompey defence allowed him time to tee up his matchwinner.

But Pompey should have equalised. With just five minutes to go a gilt-edged chance dropped to Kamara on the edge of the six yard box. But the Senegalese international marred an excellent individual performance by hooking a left-footed volley wide with only Sorensen to beat.

Stone added: "It was a great finish from Hitzlsperger, he had to pull something special out of the bag for Villa to win, but we're not scoring goals from open play at the moment, only penalties, and we should be scoring more.

"It's as simple as that, we're creating the chances but no one seems to be that natural in front of goal. We've got four good strikers but putting the ball in the net is an art in itself."

Pompey 1 - Aston Villa 2