With the US Masters behind him, Tiger Woods returned home to more important business on Monday - the failing health of his father Earl.

With his dad back home in California battling cancer and too fragile to travel, a concerned Woods made his first visit to the Augusta National Golf Club last week without his mentor.

Although Woods downplayed the impact his father's absence had on his concentration, the world number one occasionally appeared distracted during his green jacket defence, finishing in a tie for third three shots back of winner Phil Mickelson.

In fact, the 70th Masters may well be remembered as one Woods let slip away behind uncharacteristically shaky putting, including a pair of missed eagle putts from inside 10-feet that effectively stalled a final round back-nine charge.

Later in the Georgia twilight as Woods helped Mickelson slip into his second green jacket, the 30-year-old American lamented his poor putting and the absence of his father.

"I'm sure he (Earl) was watching and a little mad at me for the way I putted," Woods said. "I'm sure he knew what I did wrong."

Since jetting across the country on the eve of the Players Championship in May in the hopes of giving his ailing father a lift, Woods has not displayed the dominating form he showed early in the campaign.

In the next few months he can be expected to ride an emotional roller coaster that will test his vaunted powers of concentration.