If you have the suspect nerve of a Sergio Garcia, they will expose you.

Thursday when players tee off in the 109th U.S. Open, the Bethpage crowd will be the story as much as the famed Black course’s prohibitive length (7,426 yards), fast greens (14 on Stimpmeter), or the attempt of defending champion Tiger Woods to win another Open on Long Island.

“They say whatever they feel. And they don’t care who’s listening,” said 2008 Open runner-up Rocco Mediate. “That’s what I like about it. They just let you have it. They’re with you or they’re against you.”

When he contended for the 2002 Open at Bethpage, Garcia fielded taunts for waggling, double-clutching, and re-gripping his club. When the Spaniard flipped a single-finger response, it was clear the fans had gotten under his skin.

Seven years later, Garcia is trying another approach.

“New Yorkers are very passionate,” said Garcia. “The only thing I can say is I’ve been very fortunate to do very well here in this area. I love New York. I love the people around here.”

Other courses in the New York suburbs have hosted U.S. Opens. But private Winged Foot, Baltusrol and Shinnecock Hills have not produced the rambunctious crowds to match that of municipal Bethpage in 2002.

“I’ve never played in an atmosphere that loud for all 18 holes,” said Woods, who won by three strokes in 2002. “Everyone was so excited to have it out here on their golf course because it seemed like everyone who’s played golf in this area has played [here].”

Geoff Ogilvy, the 2006 Open champion at Winged Foot, says fans at Bethpage ask for autographs and keep talking as you sign. In a practice round on Sunday, Kenny Perry said he got plenty of unsolicited advice on reading greens.

“Everybody I saw yesterday said: ‘This is my home course, I play here all the time,” said Perry. “It’s a two-way street. If they don’t like you, they can really get on to you and drive you crazy. If they like you, that energy, that vibe there will help you play better.”

[email protected]