Ian Bell and Stuart Broad shared an unbroken century partnership to lift England to 326 for six on a compelling third day of the first Ashes test against Australia on Friday.
England eked out a lead of 261 runs in an atmosphere of great tension at Trent Bridge as controversy erupted in the final session when Broad edged young spinner Ashton Agar to Michael Clarke at first slip via the gloves of wicketkeeper Brad Haddin.
Umpire Aleem Dar did not give the all-rounder out and he refused to 'walk'. That left the tourists, who had used up their two referrals, fuming.
Bell was dropped by Haddin moments later and tensions spilled over on the pitch and the Australian balcony where coach Darren Lehmann was seen shaking his head.
The 31-year-old Bell was unbeaten on 95 at the close with Broad on 47 and England will now look to push their lead beyond 300 on Saturday.
"It was absolutely brilliant by Belly," England batsman Kevin Pietersen told a news conference. "He has proved exactly why we think he is such a fantastic player.
"I'd be foolish to say we've got enough runs already but we have a fantastic bowling attack."
The day started sedately as Pietersen and Alastair Cook continued to adopt a cautious approach after resuming on 80 for two.
Pietersen drove Mitchell Starc to the cover boundary, one of his 12 fours, to reach his half-century and moved confidently to 64.
The batsman was then distracted by a spectator moving behind the bowler's arm and dragged the next ball from James Pattinson on to his stumps as he tried to force it through the off side, ending a third-wicket partnership of 110.
Cook's four-hour vigil was over shortly after he reached his half-century, the captain edging a top-spinner from Agar to slip where opposing skipper Clarke held a fine one-handed catch high to his left to leave England in trouble on 131 for four.
It was a first test wicket for Agar who played an extraordinary innings of 98 batting at number 11 to turn the match Australia's way on Thursday.
The tourists were cock-a-hoop and the crowd fell quiet as Pattinson and Starc obtained significant reverse swing to trouble Bell and Jonny Bairstow who had to work hard to take England through to lunch on 157 for four.
Bairstow had fought for 62 deliveries to make 15 when he edged Agar to Haddin and Matt Prior joined Bell.
Australia took the second new ball and the England wicketkeeper went on the attack, punching Pattinson through cover for four to bring up the 200 and carving Siddle over backward point.
Prior struck six crisp fours on his way to 31 off 42 balls but he perished trying to hit another, pulling Peter Siddle to mid-wicket where Ed Cowan leapt to take a sharp catch above his head.
Bell brought up his half-century with two off Pattinson, reaching 6,000 test runs in the process, and England went to the tea interval on 230 for six.
Broad smeared Starc to the extra cover boundary to bring up the half-century partnership as England edged their lead past 200 before the Aleem Dar incident took centre stage.
The controversy may have affected Bell, a model of concentration for more than five hours at the crease. He played his one false stroke and was put down by a diving Haddin off Siddle.
Broad rubbed salt into Australia's wounds by cutting Shane Watson for four to bring up the century partnership, chiselled out by the two England batsmen from 213 balls.
Bell survived a huge shout for lbw off Pattinson just before the close and the right-hander will resume five runs short of his 18th test century.
"It was a long day. We were hoping to get a couple more wickets so that was disappointing," Siddle said.
"He (Bell) batted well and dug in and we couldn't crack him early. We have to come out and get wickets tomorrow and we are still in a good position - it's a beautiful wicket to bat on."
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