With play under way, early starters might be looking at the afternoon threesomes for a hint at challengers.

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Consider this trio: Webb Simpson, Padraig Harrington and Billy Horschel. They step to the tee at 1:50 p.m. ET with intentions on winning. And each has a good story to the season.

Competition at TPC Southwind is the last before the U.S. Open. Starting June 18, the world’s best golfers and qualifiers will be at Chambers Bay, a challenging course near Tacoma, Wash.

Tiger Woods and Rory McIlroy are expected at the Open, but neither is playing this week. So Mickelson is the man to watch.

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Here is the leaderboard for the St. Jude Classic.