Putting fix for Mickelson ahead of US Open

AUGUSTA, Georgia (Reuters) - Phil Mickelson tied for fifth place at the U.S. Masters at windy Augusta National on Sunday and said he had to improve his putting to do better at the next major.

Mickelson was unable to mount a sustained challenge after missing several short putts but said he aimed to fix that problem before the U.S. Open in June at Torrey Pines in his hometown of San Diego.

"I've been playing practice rounds sporadically for some time now, so it's already in the back of my mind," said Mickelson.

"Growing up there, that tournament means a lot to me, living in San Diego, playing high school matches there at Torrey. I've been out there a bunch and I've been thinking about it a lot."

Mickelson was in prime position at the halfway mark, tied for third place at five under par, three strokes behind eventual winner Trevor Immelman of South Africa.

But the world number two posted a three-over 75 on Saturday to slide off the leaderboard. A solid 72 on Sunday put him into the top 10.

"I thought that I struck the ball pretty well this week, and it's encouraging that playing the majors I'm striking the ball better than probably I ever have," said Mickelson.

"My chipping came around this week. It hasn't been where I wanted it the last couple weeks.

"The last piece is I'll spend a little more time on putting and try to get that dialed in. I think I've been neglecting it a little bit working on the ball-striking aspect.

"When I come back in a couple weeks hopefully I'll have that straightened out."

Mickelson said he had to fight hard just to make par on Sunday.

"I certainly had some chances that could have brought it lower."

(Editing by Peter Rutherford)