Phil Mickelson used to carry two drivers at Augusta National. Now, he may have a lot more options available to him.

Mickelson is considering the use of Callaway Golf's I-Mix Technology, which pairs an FT-i or FT-5 Driver head with any of a variety of shafts using a patented connector. A golfer can choose a shaft for the day based on course conditions and whether to have higher or lower launch, more accuracy or distance, or a number of other factors.

Mickelson currently uses an FT-5 driver on tour. The introduction of the I-Mix driver to his bag is likely to come this week at the Masters.

"My game is totally coming around and (I'm) starting to drive the ball well," said Mickelson last week at the Shell Houston Open, where he finished in a tie for 23rd. He used the I-Mix driver in practice rounds at that tournament.

And at the World Golf Championships-CA Championship last month, Mickelson hinted that he would carry only one driver this year.

"There's a good chance that I'll only have to use one driver and still be able to get the distance out of it that I'm looking forward to, carrying bunkers like on No. 2 and No. 8, and then hitting the carve cut shot off of 10 and 13," Mickelson said. "It allows me to have an additional club, whether it's a 3-iron that I might need on hole No. 4, or into the green on 13 or 15, or maybe another wedge for around the greens. I'm not sure.

“But the fact that it looks like I'm only going to have to have one driver this year, I'll be able to hit the shots that I needed to hit like I did in '06, to fly it up on top on 17 and get the distance that I need."

Adjustability — or the opportunity to make changes to a club as long as it is not during a round — was approved by the U.S. Golf Association for 2008. No pros have used Callaway's system, which debuted in January, in competition on the PGA Tour yet, though Ernie Els used a customized FT-i driver for two rounds at the Dubai Desert Classic on the European Tour earlier this year.