Referee´s assistant struck as Pompey´s 10-men hold on for a point

Portsmouth held on for a goalless draw at Aston Villa on Saturday despite having Sean Davis sent off, but the match was marred after a linesman appeared to be hit by a missile thrown from the crowd.

Referee's assistant Phil Sharp fell to the turf late in the second half at Villa Park and needed treatment before resuming with a plaster on his forehead.

Portsmouth manager Harry Redknapp gestured angrily towards the crowd behind the dug-out and stewards moved in to police that section.

It was an unsavoury incident which could lead to an FA investigation and severe repercussions for Villa, who were frustrated on the pitch as well after Redkknapp's side survived a nervous last nine minutes following Davis's dismissal.

Portsmouth were first to threaten when Sean Davis pounced on a weak headed clearance from Martin Laursen. The midfielder's half-volley from the edge of the box was heading in until Brad Friedel sprang across goal to make a smart save.

John Carew had the first effort on goal for the home side but the Norwegian international hooked his shot on the turn wide of a post.

Villa were beginning to take control and an inswinging Ashley Young corner picked out Carew, only for his close range effort to be blocked by Glen Johnson.

Curtis Davies should have broke the deadlock in the 17th minute. Gareth Barry curled in a free-kick to Laursen, whose flick reached Davies but the Villa defender shot wastefully over.

Portsmouth finally came to life midway through the half. Jermain Defoe shot straight at Friedel before manufacturing a candidate for miss of the season.

Peter Crouch laid the ball into the path of Armand Traore and the on-loan Arsenal star's shot smacked against a post. The rebound hit Friedel on the back and then Davies's shanked clearance fell to Defoe four yards out.

He looked certain to score but the England striker somehow managed to hook his shot high and wide.

Villa's response was immediate. James Milner forced David James to save with a hooked effort and Carlos Cuellar headed the rebound just wide.

Crouch found space at the far post to get on the end of a Glen Little free-kick late in the first half but his header flew straight at Friedel.

Neither side could find any momentum in the early stages of the second half. Villa midfielder Stiliyan Petrov provided a brief flash of inspiration when his sublime pass found Ashley Young in a yard of space but the winger dragged his low shot wide.

Villa's first significant strike on goal didn't come until deep into the second half when Young's free-kick was well stopped by James.

Carew had a late header which clipped the bar but the incident involving Mr Sharp in the closing moments cast a shadow over an otherwise forgettable match.