James Shane showed his huge potential at the UK trials

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Shane storms to 1500m win in Birmingham

One of the highlights of the UK trials this weekend for me was seeing James Shane come through to win the 1500m.

Shane took three seconds off his personal best and that lad has probably run himself, in the space of the last four or five weeks, from being a total unknown to going to the World Championships.

Nobody wants Shane or others to go to Daegu as passengers with no hope of making finals. Head coach Charles Van Commenee rightly wants a team that is genuinely competitive. We want to win medals and we know where most of those are likely to come from - but you have to be thinking about the future.

The trials mean different things to different people. For someone like Jess Ennis this is very different. This was an opportunity for her to do a bunch of events.

Other athletes come here as their last chance, while Perri Shakes-Drayton used this for strength training in two events - the 400m and 400m hurdles, of which she won both.

Van Commenee wants eight medals at next year's Olympic Games, and he reckons that target requires 15 British athletes to stand a strong chance.

Of those eight, he would include at least a couple of relay medals - certainly the 4x400m relays. On top of that, you want 10 or 12 good individual medal chances.

From what we have seen at this weekend's UK trials, there are eight or nine who fit that bill, of whom three or four have very good chances.

We are a year out, and we have already seen a year can make a huge difference. Dai Greene has made massive improvements in that time, and Mo Farah has gone to the top of the world. Van Commenee will hope three or four others fit that bill.

This weekend, all of Britain's major contenders going to Daegu for next month's World Championships - those that were here - were fine.

Triple jump world champion Phillips Idowu not competing was a disappointment but I have no issue with his decision.

I don't think there is anything wrong with people at his level deciding that, in terms of their preparation, they're better off not being here. Do we want Phillips to trot down and hop, step and jump with his heart not in it, for the sake of winning and so we can all say thanks very much for turning up?

We sometimes forget that when you're at his standard, particularly at his age, you want him to save his best for the Worlds and the Olympic Games.

At the other end of the age scale, a lot has been written about Lawrence Okoye, the 19-year-old discus thrower who now holds the national record. But he finished fifth here.

We forget we are taking about teenagers, and consistency is something you have to develop in athletics. One big performance will not win you medals.

Okoye could not perform here to anywhere near the standard he has reached and, as a result, he may well miss out on the World Championships. The selectors are in the unusual position of having so many discus throwers at the 'A' standard.

But he will either learn from that or he won't have a career. If he was 28 or 29, you'd worry, but you give your young athletes a little leeway. A one-off is fair enough as long as they know that's something they need to be able to put right.

Six years ago, after Britain won a lone gold medal and two bronze at the 2005 World Championships in Helsinki, I wrote that it was possible we would see no British finalists in athletics at London 2012.

Helsinki was bad. You say things like that because you can't believe what you've seen sometimes. However, I still think we are dealing with one or two good people in a lot of events - some of the quality here overall is not as good as you would like it to be.

But the discus, and other events like the men's 400m hurdles, show that if you can get four or five good athletes together they are bound to push each other on. If we can begin to generate high-level competition like that within the rest of the British sphere, there will be more chance of the British number one being in the world's top two or three.

Steve Cram was speaking to BBC Sport's Ollie Williams.