Updated

FORT WORTH, Texas (Reuters) - Phil Mickelson, eager to bury memories of last year, has every reason to look forward to this week's Colonial Invitational with the world number one ranking within fingertip reach.

Should the American left-hander win the PGA Tour event at Colonial Country Club on Sunday, he would take over at the top of the global pecking order from his compatriot Tiger Woods.

"It's something that we as golfers all strive to be recognized for -- as the best player," second-ranked Mickelson told reporters on the eve of Thursday's opening round at Colonial, a venue where he triumphed in 2000 and 2008.

"It would certainly mean a lot because I have not done that in my career. It would be an accomplishment I would look back on and be very proud of."

Woods, who has steadily dropped ranking points this year, is sidelined with a lingering neck injury and not expected to return to the circuit until at least next week for the Memorial tournament.

However, U.S. Masters champion Mickelson preferred not to be distracted by the rankings topic as he prepared to win another tournament on the world's most competitive circuit.

"I will probably try to downplay it typically," the 39-year-old said. "To accomplish that, I can't focus on that. I still need to go out and play like the number one player in the world, so I've got some work to do."

BREAST CANCER

Mickelson was not prepared to reflect on his life 12 months ago when he suspended his tour campaign indefinitely after his wife Amy was diagnosed with breast cancer.

"I don't really want to go back there," Mickelson said. "We are a year down the road. That was a tough time, and I'm happy that we are further down the road now."

American world number four Steve Stricker, who triumphed at Colonial last year in Mickelson's absence, was delighted to see his compatriot back.

"I thought it was the greatest feel-good story in golf when he (Mickelson) won at the Masters (in April), and seeing Amy there. I think he is going to be tough to beat here too."

Apart from Mickelson and Stricker, three other members of the world's top 10 are competing this week -- fifth-ranked Jim Furyk, Ian Poulter (sixth) and Paul Casey (eighth).

(Writing by Mark Lamport-Stokes in Los Angeles; Editing by Ed Osmond)