JOE ROOT hit a masterful attacking century as England positioned themselves for a victory push on day three of the second Test against West Indies.

Root was in wonderful touch as he reached his hundred in just 125 balls, playing with freedom and intent on a pitch that placed him on a different plane.

England had other successes - Alastair Cook and Jonathan Trott sharing the team's first century opening stand for more than two years, Gary Ballance reeling off another redoubtable 77 - but Root operated with ease on a day where others were made to work long and hard for their runs.

After 112 overs, England were 46 ahead on 345 for five, with Root 102 not out.

It was a sixth century for the 24-year-old, who also equalled the English Test record of six consecutive scores of 50 or more.

The day started with England's first century opening partnership in over two years, Alastair Cook (76) and Jonathan Trott (59) putting aside concerns around their form to post 125 at the head of the innings.

That set a firm foundation for an assault on the West Indies' mark of 299, and Yorkshire duo Root and Ballance led the way in some style as the tourists reached the final drinks break in the lead on 318 for three.

The two partnerships that underpinned the English effort were very different in complexion, Cook and Trott digging in a stoic morning session that looked as if it might hold the game back.

Instead it gave the batting side a firm base to work from, allowing Ballance and Root, in particular, to make hay as the day progressed.

It was a wonderful day for batting, with clear blue skies, negligible seam movement and a bowling attack that ground to a standstill in sapping heat.

Root's knock was the most damaging, his ability to hit the boundary boards and run hard doing most to advance the game in England's favour.

In scoring his sixth consecutive Test half-century he equalled a national record held by Cook, Ted Dexter, Ken Barrington and Patsy Hendren.

But this was also a day of triumph for Ballance, whose diligent accumulation at number three has seen him adapt with remarkable ease to the demands of Test cricket.

As Kevin Pietersen continues to vie for attention at Surrey, it might be worth pondering how he would even fit into a middle order that is being marshalled quite brilliantly by two men around a decade younger than him.

The day began with Cook and Trott on 74 without loss but still firmly under the microscope, the captain seeking a first hundred in 34 innings and his partner attempting to justify his recall after 18 months off the circuit.

The opening session saw them both pass fifty, but it was a slow grind, with 69 runs in 34 overs.

Trott did not make lunch, tempted in by Devendra Bishoo and feeding an edge to second slip.

His 59 represented progress after a nervy return in Antigua last week and should stand him in good stead for further opportunities.

Cook might also have fallen to the leg-spinner, with a marginal lbw review falling in his favour.

Instead he fell after the break, Shannon Gabriel taking two wickets in as many overs as 125 for nought turned into 164 for three.

Both Cook and Bell dragged the ball into their stumps, the skipper done by a change of angle and his deputy by a bit of extra bounce outside off.

That brought Root and Ballance together, fresh from a century stand in the second innings in Antigua.

They dovetailed perfectly once again, adding 165 at a shade under four an over to ensure the early platform did not go to waste.

Ballance was more cautious, but exploded to life in bursts, hitting three fours in 10 balls to race into the 20s and flogging Jermaine Blackwood for six.

Root was even better, knocking Bishoo's confidence with his aggression and not allowing Jason Holder to settle.

He raced past 50 in 69 balls and continued to score with impunity, a disorientated Bishoo on the receiving end of two dismissive sixes.

Root was just six deliveries in the 90s and flashed his 13th four to third man to bring up his century.