Three-time major champion Padraig Harrington needs to win this week's Texas Open or at Houston next week if he is to qualify for the Masters next month.
The Irishman has played at Augusta every year since making his debut in 2000.
Harrington is down at No 155 in the world rankings and slumped to a final-round 80 in the Arnold Palmer Invitational on Sunday, but he has not given up hope of winning one of the next two events to make it to Augusta.
"It was a funny week," Harrington wrote on his official website. "My final round was terrible and as a result my finish for the week was too, but when I look back there were a lot of positives to take from it.
"I know that seems hard to believe after I finished on five over par in a tie for 67th, coming off a final round of 80. However, I definitely saw a lot of good things during the week, things I hadn't seen for a while.
"My chipping and putting were much better.
"Last week I decided to get back to practising my putting and chipping and not spending as much time hitting full shots on the range. It definitely helped as I was more confident than I had been for a while with my short game.
The old me
"My first round was like the old me, getting it up and down no matter where I was. I wasn't able to keep it up all week but, in general, there was a marked improvement in my chipping and putting and more importantly in how I felt about that aspect of my game.
"With two tournaments left to qualify for the Masters, time is running out. I have to win one of the next three and I would love to do it here so as to sort it out quickly. I am trying hard to get to Augusta as I will find it very hard sitting at home watching it on TV."
The Texas Open is the last chance for players to climb into the top 50 in the world rankings to qualify for the first major of the year.
However, world No 53 Richard Sterne and No 55 George Coetzee are not in the field at San Antonio.
The only players who can move into the top 50 without winning in Texas are Chesson Hadley (56th) and Ryan Palmer (62nd). Everyone else who could make it to the top 50 would have to win, which secures a Masters invite anyway.
Open champion Phil Mickelson is competing in the event for the first time since 1992, when he finished joint 47th at Oak Hills Country Club in just his sixth start as a professional.
Watch the first round of the Texas Open live on Sky Sports 4HD from 7pm on Thursday.