It is said that every dog has its day and for Lee Westwood's feisty caddie Billy Foster, a self-proclaimed golfing Jack Russell, that day is now.

The straight-talking Yorkshireman has previously worked with Seve Ballesteros and Tiger Woods among others but it is only this year he has truly cashed in following fellow Briton Westwood's stunning rise to the top of the world rankings.

"If you had asked me two years ago whether I thought he could be No 1 in the world, I'd be lying if I said the answer was yes," Foster said.

"That's a testament to Lee and how he's dedicated himself and his focus and he is possibly now one of the fittest golfers out there. A few years ago that would never have been considered.

"He has put in a fantastic effort on the fitness front and is reaping the rewards. He has improved in all departments," said Foster.

"When I started working with him (in May 2009) I didn't think he'd be as good as he is now. He has moved on to another level and you feel now he is almost guaranteed to finish in the top five every single week."

The 44-year-old has caddied for years and can remember a night when money was so tight he had to sleep rough.

The globe-trotting Westwood picked up 3.2 million euros ($4.2 million) on the European Tour alone in season 2009-10 and with caddies taking a cut of between five and 10 percent, and earning bonuses for good results, that adds up to a princely sum for Foster.

"The caddying game has changed," he explained. "The first 10 years I did it I probably never made a penny.

"I remember working for (Zimbabwean) Tony Johnstone at the Portuguese Open in the 1980s and we finished about seventh and won about $1,392. I got five percent of that and had to pay for my travel, hotel, everything.

"I couldn't afford to fly in those days. I used to get overnight buses, sleep on trains and I slept in a bush one night," said Foster.

"These days I can afford to fly everywhere, stay in a decent hotel, drive a nice car. Since Tiger came along money's gone through the roof and the caddies are earning a lot more than they used to."

Foster teamed up with Woods in 2005 when the former world No 1 took him on loan from Darren Clarke for the Presidents Cup.

"We only worked together for a week," said the caddie. "It was about 10 years after I worked with Seve but that was the first time I had felt the same aura about a player since.

"I said to Tiger I would never swap lives, with all the hassle and focus on his life. You've got to appreciate how difficult it is for him.

"He was a true gentleman. His manners, and respect for me, were bizarre - everything he said was with a please and a thank you and I just thought he was true class on the golf course.

"I also remember one hole we had 142 yards to carry up a hill into a little bit of a breeze and I knew he hit a pitching wedge around 130 yards. He pulled a pitching wedge out and I said, 'You sure that's enough?', but he said it would be fine.

"It went as high in the air as it went forward and finished six inches from the hole. As we walked up to the green I asked him how he did it and he said, 'Don't worry Billy I've got another gear when I need it'. That's what makes people special."