PNicholls

A word of warning for Betfair punters - in fact, three.

The first is that you can't always trust Cheltenham form at Aintree. Admittedly, three horses won at both Festivals last year - Big Buck's, Peddlers Cross and Albertas Run - but you simply never know for sure what running at Cheltenham, the most competitive of racing environments, has taken out of your horse.

Different track, different ground, different day often leads to different results, with the form not standing up.

In addition, you never know what has happened to the horses in between.

And I can reveal here that I have had a couple of minor scares with Big Buck's and Zarkandar this week.

Big Buck's always tends to give me a scare before big races, which is very nice of him. He worked moderately on the Saturday before Cheltenham before coming out and winning his third World Hurdle.

And on Monday and Tuesday he went off his grub, so on Tuesday we gave him a blood test.

Thankfully, it came back fine and he ate up this yesterday, so we are back on track.

I don't know what we would have done had the test come back inconclusive, but luckily it didn't. I could have done without 48 hours of worry, though.

And that is before the problem we have had with Zarkandar.

He has had a bad abscess in his mouth and we have been constantly bathing it. He hasn't missed any work but of course it has been very sore, though he is a tough buggar.

But thank god it burst Tuesday morning, so touch wood it will have done his chances no harm at all.

To win big races at the major Festivals, you can do without even the slightest of setbacks and problems.

To put it into context though, I must stress that both horses have continued to work well throughout the minor scares, and are fine.

But I thought it best to let everyone know before their races.

For more exclusive Paul Nicholls articles throughout the Aintree Festival, go to http://betting.betfair.com/horse-racing/paul-nicholls/