Jacklin assesses Open chances of 'Big Four' (Reuters)

TROON, Scotland (Reuters) - Former European Ryder Cup captain Tony Jacklin, winner of the 1969 British Open and 1970 U.S. Open, assesses the chances of golf's 'Big Four' in this week's Royal Troon major.

World ranking: One

Major wins: One (2015 U.S. PGA Championship)

Best British Open finish: Tied fourth in 2015

Jacklin's assessment:

"Jason's a hell of a player. He's been playing some fantastic golf and I've no reason to think he won't be a threat this week.

"The confidence he's gained from winning seven times in the past 12 months is huge. You anticipate playing well when you've done what he has done and it puts you in a great place mentally.

"But on a course like this you can't count your…