If you’re a Tottenham supporter, surely you’ve seen the video clip.

The Seattle Sounders and Philadelphia Union are locked at one in the second half of the U.S. Open Cup final, and the Union is countering quickly for what could very well be the go-ahead goal.

Unreal first match to be at. Amazing atmosphere and a 5-3 win! Can't beat that! #COYS — DeAndre Yedlin (@yedlinny) January 1, 2015

Philly’s No. 10, Cristian Maidana, pushes the ball past the last Seattle defender at the midfield stripe before sprinting into open space – then the blur wearing Sounders lime-green enters the picture from the right.

DeAndre Yedlin had given Maidana at least a 10-yard head start, but with a cool boost of acceleration, he beats the attacker to the ball before the latter even reaches the penalty box. Yedlin wins the race so convincingly that he has time to clear the danger at a nonchalant trot.

That’s the potential, the pure athleticism, that inspired Spurs to buy the 21-year-old this past summer.

That’s the potential that persuaded United States men’s national team coach Jurgen Klinsmann to not only bring Yedlin along to the World Cup in Brazil, but to bring him on as a substitute in the final three U.S. matches in the tournament.

The World Cup was Yedlin’s turning point from homegrown Seattle prospect to an international transfer target.

The blinding pace flashed in the U.S. Open Cup video gave Portugal fits. Yedlin sparked the U.S.’ go-ahead goal against A Selecção, breaking down the right, playing in the ball that Seattle teammate Clint Dempsey eventually turned in at the near post.

His speed matched Eden Hazard stride-for-stride in the Round of 16, helping the United States survive a Belgian onslaught into extra time before the Yanks bowed out.

And his athleticism convinced Seattle to make Yedlin its first-ever “Homegrown Player” signing – Major League Soccer’s initiative to spur domestic youth development – when he was just 19. That raw potential pushed Yedlin into the Sounder starting XI almost from Day 1. He scored a volleyed goal from distance in the CONCACAF Champions League in just his second professional start.

But there’s another half of that Open Cup video, one often edited out or glossed over -- yes, Yedlin closed out the counterattack, but he’s also the one who started it.

Go back a few frames, and Yedlin mis-plays an attempted volley toward the box, popping it back over his head instead. Maidana pounces on the flubbed clearance and off he goes.

Yedlin’s two years in Seattle were about sanding down the rough edges to his game, one match at a time. He played outside midfielder through most of his youth career before shifting back to defense at Akron University.

“As a winger, he was probably a dime a dozen,” his college coach Caleb Porter, now the manager of the Portland Timbers, told the Seattle Times in 2013.

“Shift just to an outside back, and all of the sudden, he’s special. You don’t see that kind of outside back that’s as athletic as him.”

The transition hasn’t always come naturally. Yedlin spoke at length this past season in Seattle about improving both his defensive skill-set and his service from out wide.

The shift might not even be permanent. Klinsmann pushed Yedlin up into the midfield for the second half of a friendly against the Czech Republic in late October.

Whether Tottenham can solve that positional riddle, whether it can tilt the scales in favor of the good Yedlin as opposed to the flawed, remains to be seen.

But the potential is there – the evidence is right there on tape.

Matt Pentz is the Sounders FC beat writer at Seattle Times. Follow him on twitter