The ICC [Images] Champions Trophy clash between India and Australia in Mohali is a massive game for both sides, as only one of them can progress to the semi-finals.

But for one of the men at the centre of the action, the match has a degree of personal significance, whatever the result.

For umpire Steve Bucknor [Images], it is his 150th One-Day International; he becomes only the third official in the history of the game to reach that milestone, following in the footsteps of David Shepherd and Rudi Koertzen.

The list for most appearances by an umpire in ODIs looks like this:

172: David Shepherd

156: Rudi Koertzen

150* Steve Bucknor

126: Daryl Harper

124: Darrell Hair

107: David Orchard

100: Steve Dunne

[Figures up to and including October 29, 2006]

Reflecting on his achievement, the 60-year-old Jamaican said: "I never thought I would get this far, as back when I started there was the chance to stand in just a few matches every year.

- Also read: Soccer refereeing gives Bucknor the edge

"But now I can look back and think about the ICC Cricket World Cups and many other matches I have umpired and it makes me feel very proud."

ICC president Percy Sonn paid a special tribute to Steve Bucknor when he said: "To reach the top in any profession you have to be very good and Steve is exactly that.

"Not only that, but Steve has been very good for a very long time now and in an era when umpiring decisions are scrutinized more than ever before his achievement in reaching 150 ODIs is an outstanding one.

"This landmark is a tribute to Steve's skill, dedication and consistency, all qualities that are needed to be a top umpire. On behalf of the cricketing world I congratulate him on this milestone and hope he continues to show himself to be one of the game's top officials for many more matches to come."

In addition to umpiring in 150 ODIs, Bucknor has also stood in more Test matches -- 113 -- than anyone else, but cricket is not the only sport in which he officiated at the top level. He was also an international soccer referee, so was there ever a chance we could have seen him take charge of World Cup finals in cricket and football?

"Not really, and I did not leave football for cricket," he said. "It was just that I got too old for football refereeing when FIFA lowered its retirement age from 50 to 45 so that gave me the chance to focus on cricket."

It all started for Bucknor the international cricket umpire back in March 1989 when he stood in his first ODI, the match between the West Indies [Images] and India in Antigua.

The home side, led by Vivian Richards, won that match by eight wickets thanks to 117 from Gordon Greenidge and four wickets from Ian Bishop. India was captained by its current chairman of selectors Dilip Vengsarkar, who top-scored with 88.

Bucknor quickly established his reputation as a high-class official and after being named as one of the umpires for the 1992 ICC Cricket World Cup in Australasia he went on to stand in the final when Pakistan beat England [Images] to lift the trophy in Melbourne.

It was the first of four successive final appearances for Bucknor, a figure no other umpire can match.

"That first World Cup was a real highlight for me," he said. "I was only a relatively junior umpire back then and never thought I had a chance of standing in the final but I was chosen and have been fortunate enough to stand in every one since."

More than 14 years after that first final and Bucknor is still going strong. Now the senior figure on the Emirates Elite Panel of ICC Umpires, he is recognized and respected around the world for his outstanding decision-making, something that is married with an air of calm. So, what is the secret of his longevity in the game?

"Hard work, physical fitness and being mentally prepared," he said. "The hard work comes from constantly reading up on the laws and the playing conditions so you always know what you are doing.

"The physical fitness is important too because if you are not right in that area then you will struggle to do the job. That fitness for me is all about maintaining a strong mid-section of the body, the abdominal and back muscles. Standing for seven or eight hours a day is hard work but if those muscles are right then you can do it.

"On top of that you have to be mentally prepared and that means knowing about the teams you are going to umpire and also being aware of what conditions you will face and dealing with them so you can concentrate on the job in hand."

And how have things changed for umpires during his time at the highest level?

"Technology has made a big difference," said Bucknor. "When I started there was barely any television coverage in some countries but now almost everyone has access to matches. That means there are many more living room umpires now who see the correct answer to an appeal after watching ten replays.

"Umpires, in contrast, get one look at each incident at normal speed so we can be proud that we get so many decisions right."

If Bucknor maintains the high standards he has always set for himself and his profession then he still has plenty of time left at the top level -- and, in the short term, there is next year's ICC Cricket World Cup in his backyard, the Caribbean.

"That is an exciting prospect," he said with a smile. "It would be nice to stand in final number five."

As for a motto for aspiring umpires, Bucknor's is simple: "Fair play. Just concentrate on being as fair as you possibly can.

"You have to be realistic and know you will make mistakes but as long as you focus on being as fair as possible that is a real key."