Padraig Harrington: I'll take the positives from my British Open tilt

Ireland's Padraig Harrington tees off 6 during day five of The Open Championship 2015

Two-time Open champion Padraig Harrington believes he has rediscovered some form in the majors after an encouraging show in the 144th championship at St Andrews.

Since winning the 2008 US PGA Championship, his third career major, he has recorded just three top-10 finishes - the last coming joint-fourth at the 2012 US Open at Olympic Club in San Francisco, California.

Even though his seven-under total - after a disappointing final-round 75 - was only good enough for a share of 20th, the way he got himself into contention has provided optimism.

"I felt very good mentally; not great on the greens at times but very good mentally up to a certain point," he said.

"The greens kind of got a bit to me. I hit lovely shots really all the way home. Only that tee shot on 17 wasn't great but everything was pretty strong.

"I felt I hit the ball every bit as well as I needed to but I clearly didn't putt well today. I have to think about that."

Three birdies in five holes lifted him to 13 under and into a share of the lead but he hit his drive into a gorse bush to double-bogey the sixth and, although he got it back to 11 under with seven holes remaining, three bogeys and a double did more damage despite a brilliant long, curling birdie putt at the 16th.

"Things were going well and I thought (on the sixth), 'Why not take it on at that stage?' and it was disappointing to lose the ball," he said. "It wasn't the end of the world but after three-putting eight (the par three) I really struggled with the putter after that."