A leaf might cost a Web.com Tour player a PGA Tour card for 2017-18 season

Web.com Tour player Matthew Southgate experienced something on the 15th hole at the DAP Championship on Sunday that no golfer should ever experience.

At 1 over through 14 holes, Southgate faced a short birdie putt at the 15th hole.

Southgate struck the ball well when, suddenly, a leaf blew on the green and sent Southgate's ball off its line to the hole.

Southgate looked in disbelief.

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From there, a frustrated Southgate tapped in for a par... or so he thought.

Instead, Southgate breached the Rules of Golf, as defined in Decision 19-1b, which states:

If a player's ball in motion after a stroke on the putting green is deflected or stopped by, or comes to rest in or on, any moving or animate outside agency, except a worm, insect or the like, the stroke is canceled. The ball must be replaced and replayed.

Southgate did not replay the shot from its original spot, resulting in a two-stroke penalty.

To make matters worse, Southgate signed for a 7-over 77 when the round was complete. Since he hadn't applied the two-stroke penalty from that dreaded 15th hole, he had to add two more strokes to the hole for signing for an incorrect score. Instead of what he believed to be a par, Southgate actually made a quadruple-bogey 8 at the hole.

He would also bogey the 17th and triple bogey the 18th and ultimately wound up with 9-over 79 to tie for 64th.

It was costly indeed. Southgate entered the DAP Championship at ninth in the Web.com Finals -- the four-tournament series where the top 25 money winners, not already exempt, earn PGA Tour cards for the following season.

After the Sunday blunder, Southgate plummeted 11 spots to No. 20. He'll need a solid showing this week at the Web.com Tour Championship -- the final event of the series -- to remain in the top 25 and earn a PGA Tour card.