West Ham United kept their first clean sheet in 25 matches in a battling draw with Portsmouth.

Portsmouth manager Tony Adams would have been devastated at the sight of Lassana Diarra limping out of the contest early on, he would otherwise have been delighted with a match which saw the best chances fall to former Hammers striker Jermain Defoe.

Although the Hammers dominated the bulk of the second half and Craig Bellamy hit the crossbar with a terrific free-kick they were lucky to survive some magic moments from their former striker Defoe who hooked an early half-chance over and forced three fine saves from goalkeeper Robert Green.

Pompey's cause was handicapped when they lost midfield dynamo Lassana Diarra through injury after less than 20 minutes having started without the injured Sol Campbell and Niko Kranjcar, but the result was surely well received by their new manager Adams who scored his first away win at Sunderland last week.

West Ham's early pressure briefly pushed Pompey back and the visitors had a big escape when Herita Ilunga picked up possession on the left and curled in a lovely cross which the unmarked Carlton Cole just could not reach six yards out.

Pompey could have taken the lead in the 10th minute when Glen Johnson capped a penetrating run on the right by slipping a ball into the box for Defoe, who just got to it before goalkeeper Robert Green but could only hook it over the bar.

Pompey pushed forward for a spell and Green was required to make a good save to deny another impressive run and shot from Johnson.

Defoe then challenged for Diop's through ball which spun away into the path of Crouch, who looked certain to score until Ilunga's challenge did just enough to put him off.

Zola brought on Matthew Etherington and Julien Faubert early in the second half but they were lucky not to be out of the match after two sublime moments by Defoe.

In the 48th minute he took Traore's pass down the left, lost Lucas Neill and cut in to force a flying save from Green with a right-foot shot.

Two minutes later Defoe seized a long ball out of defence, shrugged off Matthew Upson and narrowly failed to lob Green who stretched to tip the ball away.

Noe Pamarot gave away a soft free-kick on the edge of the area but Craig Bellamy's set-piece clattered back off the bar and James had to smother Jack Collison's follow up for his first real save in the 53rd minute.

James was not troubled by tame efforts from Bellamy and Cole soon afterwards but Hammers were seeing more and more of the ball.

West Ham started to look a little more menacing with Collison causing problems from midfield especially when he broke and fired just wide.

Pompey were threatening again when Defoe wriggled into the area and forced a corner with a low shot which was deflected wide. The visitors looked comfortable and stand-in captain Distin easily saw off Cole as the West Ham striker tried to muscle his way through from the left - the defender timing his challenge to perfection to earn a goal-kick.

Cole produced a cute reverse ball at the other end but Bellamy's shot lacked the power to beat James.

There was real danger though in the 53rd minute when Pamarot gave away a soft free- kick on the edge of the area for a foul on Behrami and Bellamy's set-piece strike clattered against the bar.

It was the closest the home side had come to scoring so far and manager Zola was encouraged to send on Julien Faubert for the more defensive Ilunga and push Bellamy further forward in support of Cole.

Etherington's pace and ability to find width was beginning to stretch Pompey's defence but he could not find a finisher for his crosses. Bellamy and Cole both produced tame efforts that barely tested James and Pompey were always poised to strike on the break. Defoe wriggled clear from a Traore pass but slipped as he tried to steer an angled effort beyond Green.

West Ham looked for a late winner as Pompey's defenders and midfielders tired but it was striker Crouch who was taken off with Kanu the replacement on 75 minutes.

And with seven minutes left the Nigerian nearly set it up for Defoe who side-stepped Upson but saw Green block his angled shot.

West Ham's late pressure was intense but largely incoherent and Pompey's defence stood firm.