Yorkshire duo Joe Root and Tim Bresnan denied Australia a wicket on the third morning of the second Ashes Test at Lord's as England tightened their grip on the match.

Ashes-holders England were 114 for three in their second innings -- a lead of 347 runs -- at lunch on Saturday.

Opening batsman Root was 63 not out and nightwatchman Bresnan 32 not out, with the county colleagues' unbroken fourth-wicket stand so far worth 84.

Their partnership meant Australia, shot out for just 128 on Friday, already needed to surpass the Lord's Test record fourth innings victory total of 344 for one made by the West Indies against England in 1984, which featured Gordon Greenidge's unbeaten double century, if they were to pull off an astounding win.

England, 1-0 up in the five-match series after last week's 14-run victory at Trent Bridge, resumed Saturday on 31 for three, a lead of 264 runs.

Peter Siddle's three wickets late Friday saw England captain Alastair Cook, Jonathan Trott and Kevin Pietersen all out cheaply.

But Root, 18 not out overnight, eased the first ball of Saturday's play, from Siddle, through midwicket for four.

After two days of blazing sunshine, conditions were overcast for the first time and offering a hint of swing.

Root, however, drove James Pattinson through the covers for four in a style reminiscent of former England captain Michael Vaughan, who played for the same Yorkshire club side as the 22-year-old.

Bresnan took 30 balls to get off the mark while he denied Australia the joy of an early breakthrough Saturday.

He subsequently took two boundaries in as many balls off Siddle, the first edged short of third slip and down to third man with the second flicked just wide of midwicket.

The Yorkshiremen continued to frustrate Australia's six-strong attack, Bresnan driving Ryan Harris between point and cover for four.

Root then deliberately guided all-rounder Shane Watson behind point for another boundary.

But he topped that shot with a textbook on-driven four off Siddle that sped over the Pavilion rope.

Bresnan's three off left-arm spinner Ashton Agar brought up a fifty stand in 134 balls.

Soon afterwards Root completed his own fifty, in 122 balls with seven fours, and then struck Pattinson for a classic back-foot forcing shot to the point fence.

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