Vaughan must guard against leaning too heavily on Harmison

The single most important development in England's cricket over the last 12 months has been the emergence of Steve Harmison as the genuine article. He has become a high-class fast bowler, having taken 49 wickets in seven and a half Test matches since the end of last season. For all that, Michael Vaughan must be careful not to overload him. This will always be a temptation, especially when Simon Jones is not there to support Harmison.

The single most important development in England's cricket over the last 12 months has been the emergence of Steve Harmison as the genuine article. He has become a high-class fast bowler, having taken 49 wickets in seven and a half Test matches since the end of last season. For all that, Michael Vaughan must be careful not to overload him. This will always be a temptation, especially when Simon Jones is not there to support Harmison.

In the two and half Test matches which have completed against New Zealand in this series, Harmison has already bowled 144 overs. This figure will be at least in the 160s by the end of the match and there are still four Test matches to come against the West Indies which, if this rate is maintained, would almost certainly produce upwards of 200 more overs - taking Harmison's tally of Test overs for the season close to 300.

Although Harmison's run-up and action have smoothed down noticeably in the last year, his action is still more physical than some fast bowlers who seem to do no more than purr up to the wicket. An over rate like this is going not only to put a strain on Harmison's body, it is also going to make him an extremely tired young man.

Vaughan must be careful to pace Harmison even though he will always be sorely tempted to turn to him whenever two opposing batsmen begin to build a partnership. On this flat Trent Bridge pitch Harmison always looked the most likely of the England bowlers to take a wicket even though his final figures of 3 for 80 were not particularly startling.

Test matches come thick and fast these days, so a fast bowler's lot is inevitably an increasingly hard one. In 1932-33, in the infamous "Bodyline "series, Harold Larwood bowled 220 overs in the five Tests for his 33 wickets. In 1963 against the West Indies Fred Trueman sent down 236 overs in the series for 34 wickets and in 1948 against England Ray Lindwall got through 222 for his 27 wickets - and all three of them bowled their overs at a much quicker rate than they do today.

The fast bowler's payload has obviously increased with the rise in the number of Tests. It is therefore imperative that in the instance of Harmison, Vaughan protects him all that he reasonably can. It is also important that England's main strike bowler does not play in all the many one-day games that England now play.

The coach, Duncan Fletcher, will be acutely aware of this and must use, as one is sure he will, the authority that a central contract gives him over Harmison to ensure meaningful rest. There must be no question of an early burn-out with Harmison.