OXFORD United ground out a valuable point as they held in-form Portsmouth to a goalless draw at Fratton Park.

The home side had scored nine goals in their previous two games, but could not find a way past a hard-working, well-drilled visiting side.

Goalkeeper Ryan Clarke made several good saves in the first half, spectacularly denying both Jed Wallace and Matt Tubbs.

He had less to do after the break, but was thankful for one superb tackle by Jake Wright late on.

At the other end United rarely threatened, but they will be satisfied with a point.

The teamsheet showed one change from the 3-0 win against Mansfield Town a week earlier.

Joe Skarz had recovered from a hamstring strain, so replaced Sam Long at left back.

Portsmouth came into the game as Sky Bet League Two's form side and they started brightly.

It took the combined efforts of Skarz and Wright to block a shot from Ryan Taylor inside three minutes, after a clever lay-off by Matt Tubbs.

Danny Hylton responded quickly with a long range effort which Pompey goalkeeper Paul Jones gathered at the second attempt.

It was a rare moment of attacking threat from United in the opening 20 minutes.

They were on the back foot and gave Portsmouth room to play, which they gratefully accepted.

Tubbs and Taylor sent efforts just off target in the space of 60 seconds.

The best chance of the spell came in the 16th minute, when Alex MacDonald gave the ball away cheaply to Jed Wallace, whose low shot was superbly tipped round the post by Ryan Clarke.

Gradually, though, United closed the spaces and gained a foothold in the game.

Their best moments came down the right flank, from where a Hylton cross just missed Patrick Hoban and Callum O'Dowda.

The resulting corner fell to Hylton, who got to the ball and was then caught, but referee Darren Deadman waved away United's calls for a penalty.

The visitors had succeeded in making the game more even, although Portsmouth continued to forge all the best chances.

Paul Robinson should have opened the scoring just after the half-hour mark, but the centre back could not keep his header down from Dan Butler's excellent in-swinging free-kick.

Clarke was forced to make two saves from headers late in the half.

His stop from Taylor was routine, but the tip over from Tubbs a minute later was superb to ensure the sides went in level at the break.

The interval gave United welcome respite, but before long they were having to soak up pressure once more.

Tubbs dragged a shot wide after Johnny Mullins could not cut out a chip over the top, while Wallace hammered a ferocious shot just over from 18 yards at the next attack.

The home side may have been making all the chances, but their supporters grew increasingly agitated at the scoreline.

United barely threatened as an attacking force, aside from one wild shot from MacDonald.

But they worked extremely hard out of possession to harass Pompey and Clarke, who had been kept very busy before the break, was rarely called upon.

The back four were not seriously opened up until eight minutes from time, when Jake Wright slid in brilliantly to deny Taylor ten yards out.

There was still plenty more defending to be done, but United's rearguard action held on for a valuable point.

Portsmouth: Jones, Devera, Robinson, Chorley, Passley (Barcham 75), Atangana, Wallace, Hollands, Butler, Tubbs (Westcarr 80), Taylor.

Unused subs: Poke, Webster, Ertl, Fogden, Chaplin.

Oxford Utd: Clarke, Baldock, Mullins, Wright, Skarz, MacDonald, Collins, Ruffels, O'Dowda (Roofe 70), Hylton, Hoban.

Unused subs: Ashdown, Dunkley, Rose, Rasulo, Long, Roberts.

Referee: Darren Deadman (Cambridgeshire).

Attendance: 16,355 (1,292 visitors).