|US PGA Championship|
|Venue: Whistling Straits, Wisconsin Dates: 13-16 August|
|Coverage: Live radio commentary on BBC Radio 5 live sports extra and online from 20:00 BST on 15 August and on BBC Radio 5 live and online from 20:00 BST on 16 August. Live text commentary of all four days online.|
Jamie Donaldson admits time is against him to win one of golf's major championships.
The Welshman, 39, has failed to be in contention in any of the three majors this season, and has managed just two top 10 finishes on the PGA Tour.
"If I'm going to challenge for a major it's now or never," he said before this week's US PGA Championship.
"The game has been there or thereabouts but for one reason or another it hasn't been happening."
Donaldson's best finish at a major came at the 2012 US PGA when he finished tied seventh at Kiawah Island in only his third appearance in a major tournament.
He has managed to finish inside the top 15 in only once in the following 10 majors, though, missing the halfway cut on four occasions.
This week's venue, Whistling Straits on the banks of Lake Michigan, resembles the links-type conditions at Kiawah Island and tradition Open Championship courses, and Donaldson believes he can take advantage of the layout to be in contention.
"I've got to play my absolute best golf to enable me to beat what will be a world-class field. I do believe I've got that in me," he said.
"I just need to tighten up a few areas and put it all together in one week. It's a links golf course on the coast and I've always enjoyed playing that sort of golf."
This season, Florida-based Donaldson has failed to recreate the type of form that secured him a place on Europe's winning Ryder Cup team in 2014.
He has finished in the top 10 twice on the PGA Tour, while his best on the European Tour is a tie for 20th at the French Open.
"Maybe I've been trying to play both tours and it's been a little bit difficult," he admitted. "But you live and learn from it and get on with it."
Ryder Cup incentive
Donaldson will play alongside American pair Harris English and James Hahn in Thursday's first round at Whistling Straits, starting at 13:55 BST.
Not only is rediscovering his best form crucial as he aims to win this week, but Donaldson is also conscious that the race to qualify for the 2016 Ryder Cup starts in the first week of September.
"The points start in a couple of weeks so now's the time to start playing well," he said.
"You've got to play really well for a calendar season. I did that last time so there's no reason why I can't do it again."