Ashes 2013: Jonathan Trott decision concerns England

England asked the International Cricket Council for clarification after the controversial umpiring decision that saw Jonathan Trott given out lbw for a golden duck.

On another extraordinary day at the first Test, Trott was given not out by on-field umpire Aleem Dar but dismissed by third umpire Marais Erasmus despite the key HotSpot camera angle being unavailable to the official.

England ended the day 80-2, a lead of just 15, after an early Australia collapse was followed by a remarkable fightback.

Pace bowler James Anderson said: "Trotty hit the ball and was given not out on the field. I'm not quite sure what went on after that. It's pretty disappointing really."

England believe Erasmus should not have overturned the on-field umpire's decision with the critical replay not available to him.

They asked ICC match referee Ranjan Madugalle for clarification over the decision review process.

ECB chairman Giles Clarke also spoke to ICC chief executive Dave Richardson about the issue on Thursday evening, but there was no formal apology from the governing body.

Anderson said: "He did hit it. It is frustrating that it got overturned,"

"We're all for technology, because since it's come in more decisions are given out correctly than wrongly. From our point of view we want it; whatever has gone on today provides a couple of talking points, but on the whole we're happy to have it."

Warren Brennan, Hot Spot's inventor, told ESPNcricinfo that the issue was down to "operator error". "My operator did not trigger the system in order to cater for the Trott delivery," he said.

"Instead the operator sat on the Root delivery in order to offer a replay from the previous ball and did not realise until it was too late.

"Simple mistake, something that anyone could have made but my Hot Spot operator has worked on the system since 2007 and to my knowledge this is the first serious mistake he has made."

The day was dominated by a brilliant 98 from teenage Test debutant Ashton Agar, who in a record partnership with Phil Hughes took Australia from 117-9 - a deficit of 98 - to 280 all out - a first-innings lead of 65.

Agar made the highest score by a Test number 11, just a few months after turning out for club side Henley CC.

He said: "When I walked to the crease I was thinking we were in a little bit of trouble, but the wicket was good.

"Phil told me to take it ball by ball. We just played the moment and forgot about everything else.

"It was good fun, exciting and I enjoyed it. I have always tried to play freely and naturally and I don't really get too nervous. There are a lot of people who would love to be doing what I'm doing."

Agar could have been dismissed for just six, a stumping appeal by Matt Prior off Graeme Swann being contentiously turned down by Erasmus.

Anderson admitted: "I thought it was out. I saw it on the big screen, but it's hard to tell sometimes. Matt thought it was out.

"But I think he and Hughes played really well. They played their shots when they could and really put us under pressure. On debut he played brilliantly, and really did frustrate us for a while."

Agar fell two runs short of what would have been an extraordinary century, his eventual dismissal to Stuart Broad drawing genuine sympathy even from the home crowd.

"I was conscious of being in the 90s but I still felt relaxed and wanted to do my best for the team," he said.

"I tried to hit that last ball a little flatter, I was a little disappointed not to get a hundred but I didn't think I would get 98 when I walked out there so I can't complain too much. I was still pretty happy that me and Hughesie could give the boys a bit of a lead."

Despite losing Trott and Joe Root to slip to 11-2 in the second innings, England recovered through an unbroken partnership of 69 between captain Alastair Cook and an uncharacteristically restrained Kevin Pietersen.

Anderson said: "The pitch doesn't look to be deteriorating too much. We saw a few balls that spun from Swanny, but nothing from the seamers has gone up or down.

"First and foremost we've got to bat very very well in the morning to get in any sport of position to win this game."