For me i'd say

1. John Force - 14 time NHRA Top Fuel Funny Car Champion first and only driver so far to win 10 Championships in Top Fuel. Set new standards/records throughout his racing career and still doing so as a team owner.

2. Wayne Gretzky - All time greatest player in NHL history only playr to score 200pts in one season a feat h achieved 4 times. All time leadings pts scorer

3. Ayrton Senna - Master of F1

4. Sir Steven Redgrave - Gold at 5 consecutive Olympics says it all

5. Babe Ruth - Dominated Baseball in his era

Not really old enough to know about the true greats of many sports but the 5 greatest sportsmen I have been lucky enough to watch are:

Shane Warne- A true character on and off the field and could do things with a cricket ball that its unlikely will ever be replicated
Michael Schumacher- Think of Formula 1 in the last 10 years and 1 name towers above all others whether people liked him or not he was the best for years
Floyd Mayweather Jr.- Not only a boxer that is almost literally untouchable but I have had the honour of meeting him and he is a real gent
Phil Taylor- Probably responsible for darts being the spectacle that it is now. A million miles ahead of anyone in darts.
Tiger Woods- Modernised golf and opened it to new audiences


Probably not the greatest ever in some cases but as I say, in my lifetime these are the greatest.

Again from my lifetime (1962 onwards):

1. Steve Redgrave (over 16 years at the very, very top, and in no easy sport either).
2. Muhammad Ali - Nuff said.
3. Eddie Mercx
4. Merlene Ottey (girls count too don't they?)
5. Lance Armstrong.

A top 25 in no particular order would have been easier to decide!

Lance Armstrong
Phil Taylor
Valentino Rossi
Tiger Woods
Roger Federer

Other come close like Maradona, Warne, Tendulkar, Botham, Ayrton Senna and Steve Redgrave.

Ali
Botham
Maradonna
Taylor
Federer