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

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

Jacob Skov Olesen and Haotong Li held the early Thursday lead at 4 under while Mickelson, 55, had his lowest opening round in an Open since 2016.

The British Open is underway at Royal Portrush in Northern Ireland. Two-time champion Padraig Harrington of Ireland had the honor of the opening tee shot. Xander Schauffele of the United States is trying to become the first player since Harrington in 2007-08 to win the Open in successive years.

Pidgin Harrington of Ireland looks to play out of a bunker on the 13th green during a practice round for the British Open golf championship at the Royal Portrush Golf Club, Northern Ireland, Tuesday,