We all know players who seem to always get it done under pressure. More likely, they just look good by comparison with the golfers around them who are collapsing. Putting seems to exaggerate this phenomenon. When that putt on the last hole falls or doesn't, the player's reputation on the greens is set for life.
But you can do something to boost your chance of putting well in stressful situations. Develop a pre-putt routine, and stick to it no matter what's on the line. I don't care if you take one practice stroke, two or none. I don't care if you look at the hole once, twice, three times—whatever. The key is doing what feels right to you when there's no pressure, and then doing it the same when there is. That's a good routine.
Tiger is the best pressure putter I've ever seen, and his routine is unwavering. You can put a stopwatch on him on the first green and the last, and he'll take the same amount of time doing the same things.
Most golfers tend to slow down when they get nervous. Yes, there are those who speed up to get it over with, but most take extra practice strokes, extra looks at the hole, more time reading the green or just standing over the ball. It might feel like you're asserting more control, but you're only giving yourself time to second-guess.
I can't tell you the perfect routine for you, but I can tell you what works for me. I take one practice stroke, long and loose to relieve tension, then I aim the putterface precisely down my starting line. Once I have the face in position, I build the rest of my setup around that. Finally, I take one look down the line, then go. I'm a confident putter, and my routine has a lot to do with that.
Go out and experiment with different routines, and see what feels comfortable. Then work to make it part of your game. You'll hole more clutch putts.
TIGER'S DRILL FOR CONSISTENCY
When I worked with Tiger, he used to do this drill all the time. Pick a five- or six-foot putt, aim the putterface at the hole, and stick tees just outside the heel and toe (below). Practice stroking putts. The tees will give instant feedback: If you hit the outside tee, you looped the putterhead to the outside on the forward stroke; hit the inside tee, you looped it inside. Nothing beats making square contact when it comes to holing putts.