England benefited from the controversial technology decisions which bewildered their West Indian opponents as they attempted to level the series in the fourth Test.

Two of the four dismissals on the third day at the Kensington Oval were highly dubious, made after the intervention of television umpire Daryl Harper.

The International Cricket Council's referral system came under scrutiny in the first Test in Jamaica and did so again today after Shivnarine Chanderpaul and Brendan Nash were on the wrong end of harsh leg-before decisions.

Upon Nash's dismissal, West Indies coach John Dyson and manager Omar Khan appeared to visit match referee Alan Hurst's room - they returned back up the steps to the home dressing room around 15 minutes later.

West Indies closed on 398 for five after Australian official Harper's contentious backing of two lbw shouts which both appeared to be going over the top.

Fast bowler James Anderson was the beneficiary of the first when Chanderpaul offered no stroke to a delivery which shaped back into the left-hander.

Zimbabwean official Russell Tiffin adjudged Chanderpaul out for 70 and despite the use of technology, which suggested the ball was sailing over the stumps, Harper upheld his colleague's view following a challenge.

West Indies subsequently lost any further right of appeal to future umpiring decisions in the innings, having already used up one for the dismissal of opener Devon Smith.

Then, at the end of a quickfire stand of 54 between centurion Ramnaresh Sarwan, who finished unbeaten on 184, and Nash, the latter was involved in two more leg-before appeals from off-spinner Graeme Swann.

Both came with Nash on 33, and both were initially turned down by on-field official Aleem Dar.

Both were virtually identical in terms of height, and technology argued in the batsman's favour on both occasions, but although England were unsuccessful in their first review, Dar altered his decision for the second to spark West Indian protests.

Already upset with the termination of a fourth-wicket stand of 122, made in 37 overs, between Guyanese pair Sarwan and Chanderpaul, which allowed England a go at left-hander Nash with the second new ball, it left the hosts five down with 66 still required to avoid the follow-on.

Any chance of that being enforced in this run-heavy contest was obliterated in the final hour, however, as Sarwan passed 150 for the second time in his career and Denesh Ramdin made a nuisance of himself.

Sarwan batted throughout the third day to extend his rich vein of form.

This was his third and most imperious hundred of the series, following previous scores of 107, 94 and 106.

A quick single to mid-on off Graeme Swann took the West Indies batsman to a 14th Test hundred as England once again struggled to locate a weakness.

They failed to take a wicket at all, in fact, during the middle session as the hosts made the most of the flattest of batting tracks.

England's prospects of dismissing the hosts twice to level the series were boosted before lunch when off-spinner Swann claimed two victims.

Andrew Strauss' team endured a fruitless first 50 minutes of the third morning until the introduction of Swann, who struck with just his second ball from the Joel Garner End.

England's breakthrough took what seemed an eternity to be ratified after opener Smith, who rode his luck on the way to a first fifty in 24 Test innings, propped forward and was struck on the pad in line with off stump.

Dar agreed that the ball would have gone on to hit the stumps but Smith opted to challenge the decision after lengthy consultation with second-wicket partner Sarwan.

Their chat and the review of the decision by Harper meant a five-minute stoppage in play before Dar confirmed his original verdict, and West Indies lost one of their two referrals in the innings.

Requiring 19 wickets on the final three days to level the series with one to play, when West Indies resumed on 85 for one, the tourists struggled for breakthroughs in the same manner as their opponents had during a first innings of 600 for six declared.

They plumped for a change in tactics first up this morning with Stuart Broad and Ryan Sidebottom both banging the ball into the pitch rather than searching for swing.

Sarwan, the form batsman of the series, raced to his fifty inside three overs this morning, cracking Broad for two fours through the off side in the opening over.

But Swann preyed on the weakness at the other end, having Ryan Hinds in trouble prior to a delivery pitching on middle stump and straightening as it struck the pad.

This time there was no umpiring challenge and it provided the tourists with a fillip as they headed in for the first interval.

Chanderpaul shed his early-series rustiness by getting off the mark first ball with a cover drive for four and found the gaps with his customary aplomb during two-and-a-half hours at the crease.

The ease with which Sarwan played - he hauled Swann for a big six over midwicket and upper-cut Anderson for another - spelt out the size of England's task in attempting to level things at 1-1.