An early spring and rain in the forecast could lead to a \"birdie-fest\" at the 76th Masters at Augusta National this week and open the door for an upset winner, Phil Mickelson said Tuesday. The three-time former winner of the year\'s first Major joined other Masters hopefuls in remarking on the relatively lush conditions of the fairways and the softness of the much-feared greens. Asked how he fancied his chances after five days of preparations on the course, Mickelson, who will be playing in his 20th Masters, admitted that he did not have much of an idea what was going to happen. \"It seems that some of the planning I have made may go by the wayside. As soft as the golf course is, you can fire at a lot of the pins. The greens are soft,\" he said. \"I don\'t want to say they are slow, but it\'s just not the same Augusta. It\'s wet around the greens, and there\'s no fear of the course. You\'ve got to attack it this week. \"Unless something changes, and I know they have SubAir (greens drying system) and hopefully they will be able to use it, but unless they change it, it\'s going to be a birdie fest.\" That, he continued, would negate much of the advantages enjoyed by players such as himself and Tiger Woods, playing in his 18th Masters, who have put in their time at Augusta National and know the course like the back of their hand. \"A lot is going to depend on how soft the course is, how aggressive you can be. I think that if it plays like this, that there won\'t be the big mistakes made by any of the young players,\" he said. \"I think that it will be a crowded leaderboard. \"But if there\'s some firmness that comes out and the green speeds get a little bit quicker and get a little bit firmer, I think we will see some of the young players make some mistakes that will cost them the tournament and the experienced players who position the ball properly and vary their risk/reward shot making, I think they will have an easier time staying on top of the leaderboard.\" Mickelson won the third of his green jackets here in 2010 with a storming final round that included back-to-back eagles at 13 and 14, but he struggled in the second half of the year after being diagnosed with psoriatic arthritis. He had a slow start to 2012, but a confidence-boosting win at Pebble Beach set up a run of three top 10 finishes in his last five tournaments. That has left him full of confidence coming in to to what he describes as his favorite week of the year. \"For me personally, I like how I\'ve kind of built into this week,\" he said. \"I started at Bay Hill to play some good golf but hit a few loose shots. Eliminated a lot of the loose shots last week and steadily got better. \"I had three days last week here on the course, as well. I feel like I\'m playing well and I\'m looking forward to this week.\" Mickelson also spoke about the honor that will be bestowed on him next week when he is to be enshrined into the golf Hall of Fame at Ponte Vedra, Florida, at the age of 41. He admits that he has mixed feelings over the matter. \"I like the Hall of Fame as an opportunity to reflect on your career, but I am still at the stage where I\'m looking forward to other opportunities and other tournaments,\" he said.