Maybe it's just one round, but Thursday at The Open, 50-somethings Lee Westwood and Phil Mickelson shot under par.

So it came as a bit of a jolt for American audiences who woke up Thursday morning to see Lee Westwood near the top of the leaderboard at the British Open. (Also up there: Phil Mickelson, who outdueled Westwood in 2010 at the Masters. Fifteen years ago.)

Phil Mickelson, Justin Leonard and Lee Westwood are offering reminders that the British Open doesn't discriminate against older players