Jonathan Agnew: Sam Robson lets golden opportunity go begging

Sam Robson has only passed 50 once since making his maiden Test hundred

In any international sporting career an opportunity comes along that you have to grab.

Mine came at Old Trafford in 1985 when I was recalled to the England team to face Australia. It was a huge chance to prove I belonged in the Test side but I failed to take it.

At The Oval on Saturday, Sam Robson had to convince people that he was the right person to open the batting for England in the long-term, but he simply could not do it.

He had played well on Friday to reach 33 not out and set himself up for a big score. He was moving his feet nicely and struck some eye-catching drives.

Saturday was a good day for batting with the sun shining and the pitch showing few of the demons that had so tormented India the day before.

Robson, however, could only add four to his overnight score before he played around a straight ball from Varun Aaron and was bowled.

England went on to enjoy another dominant day as they reached 385-7 at stumps for a lead of 237, but the manner of Robson's dismissal left the selectors scratching their heads.

To be bowled by a full, straight delivery that wasn't even at express pace just should not happen to an opening batsman.

Anyone can make a mistake but when people are already questioning your footwork outside off stump because you keep nicking to the slips, you don't want to get out like that.

Robson made the perfect start to his Test career with a hundred against Sri Lanka in Leeds.

Sam Robson on his way to his first Test century against Sri Lanka in July

But the way he has been getting out since then has revealed some serious technical flaws that would be ruthlessly exposed by Australia in the Ashes next year.

His failings mean England's search for an opener to replace Andrew Strauss goes on and leaves the selectors with a problem when they come to picking the squad for England's next Test series in the Caribbean in April.

There is so little first-class cricket between now and then either for Robson to redeem himself or for someone else to really stake their claim. So where do they turn?

I have some sympathy for Michael Carberry because he had a really tough time in the winter against Australia.

He stuck at it but became so immersed and so shackled that he seemed to forget how to score runs and his innings in Melbourne, when he scored 12 runs off 81 balls, suggested his mind was shot.

He then made some ill-advised comments about the selectors when he got back, but I understand there has since been a clearing of the air and perhaps he does deserve another chance.

Nottinghamshire's Alex Hales has also been mentioned as an option.

Clearly, Hales needs to get into the one-day side before he can be considered for Test cricket, but he has been scoring some runs in the Championship this season after a terrible 2013 campaign.

I think the selectors will be reluctant to pick him, but it may be that by playing in the one-day side and succeeding that he can force his way into the Test team. If he has a great World Cup and is full of confidence and is shouting out to be picked then it is possible.

There is a situation vacant at the top of the order that England still need to address but one temptation they must resist is moving either Gary Ballance or Joe Root up the order.

The Yorkshire duo are enjoying golden summers and have made the number three and number five slots their own.

Ballance, who scored 64 on Saturday and now has 503 runs in the series at an average of 71, showed his confidence with a lovely ramp shot to reach his fifty, but I also loved his reaction when Ian Bell walked out to bat.

Gary Ballance and Joe Root scored 64 and 92 respectively

Bell is one of the most experienced batsmen in the team but Ballance made a point of going over to talk him through what was going on out in the middle.

He's not a shy young rookie. He clearly feels he belongs in the team, and he does.

Root is made to bat at number five. He can knuckle down and play himself in, but has the talent to go through the gears when the time is right.

He showed exemplary footwork off the front and back foot and should complete a richly-deserved third hundred of the summer on Sunday.

Jonathan Agnew was speaking to BBC Sport's Sam Sheringham.

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