The Ashes 2013: An erratic, absorbing start to the series

My biggest worry going into the Ashes was that the anxious mood in the England camp would spill over into their play - and that is exactly what happened on an enthralling opening day at Trent Bridge.

After winning the toss on a dry pitch, they looked tight and pressurised with the bat as they were bowled out for just 215 by Australia, who reached 75-4 at the close.

When England are at their best, they rely on the composure of their top order to lay a platform and the confidence of players such as Kevin Pietersen, Ian Bell and Matt Prior to pile on the runs.

On Wednesday, however, every member of the team seemed to allow nerves to interfere with their performance and affect their shot selection.

Alastair Cook chased a wide ball, Jonathan Trott dragged onto his stumps, Jonny Bairstow played across the line and Matt Prior swatted a short ball to point.

Australia's Peter Siddle hit top form to take his fourth five-wicket haul in 11 Tests against England

Of the frontline batsman, only Joe Root and Pietersen were really dismissed by decent deliveries, the former yorked and the latter drawn into playing at an away-swinger.

The Australian bowlers did manage to get the ball to move through the air, but not to any great extent.

Mitchell Starc overcame his early jitters to bowl reasonably well but the star was Peter Siddle, who once again ran in like a man possessed all day.

He is a wholehearted bowler who will give his all and it was a nice reward for him to end up with five wickets, one fewer than he managed on the opening day of the 2010-11 series in Brisbane.

Just as they were in the Lord's Test against New Zealand earlier this summer, England's batsmen's blushes were spared by the bowlers as Steven Finn and James Anderson ripped through Australia's top order.

The performance was all the more impressive given that Stuart Broad, who was struck on the shoulder while batting, was unable to play any part.

England must hope that his bruise does not develop into a pull or a tear so that he can come back on Thursday and help them finish off the Australian innings.

The bland, dry surface is not the type of pitch we are accustomed to seeing at Trent Bridge, but it does betray England's desire to prepare wickets that will assist Graeme Swann.

We already know that the wickets at Old Trafford and The Oval will turn, so Australia may have to rustle up another spinner pretty quickly.

All in all, this was an erratic display from both sides, which made for an absorbing day of cricket.

The build-up was fantastic with the national anthems, the fireworks and the Red Arrows and the crowd really came to life when Finn was on a hat-trick in the evening session.

The feeling of that wall of noise echoing around the ground and shaking the stands was spine-tingling, and although it is not the traditional way to watch cricket in England, it is certainly very infectious.

Jonathan Agnew was talking to BBC Sport's Sam Sheringham

Listen to Jonathan Agnew and Geoffrey Boycott's analysis of each day's play on the Test Match Special podcast.