CAPTAIN AMER­ICA Chris Evans drove the guys wild when he made a surprise visit to a West Hollywood gay nightclub wearing a form-hugging shirt and jeans.

The “Avengers” star dropped by the trendy club Eleven to help celebrate the 29th birthday of his out-of-the-closet brother Scott, revealed an eyewitness.

All eyes were on hunky Chris as he approached the bar.

“The guys there swooned,” said the source. “And when he came up behind Scott, hugged him and shouted ‘Happy Birthday,’ it made his brother’s night.”

Scott, who played a gay cop on the daytime soap “One Life to Live,” considers his A-list older brother “a supportive and amazing role model for gay acceptance,” said the source.

As The ENQUIRER reported last year, Chris has posed for gay beefcake shots in the past and has admitted to having a “man crush” on Brad Pitt.

But he also has quite an eye for the ladies! He dated Jes­sica Biel for five years and has also been linked to “Friday Night Lights” actress Minka Kelly and “Laguna Beach” beauty Kris­tin Cavallari.

Chris – who’s comfortable with his homosexual fan base, due in part to his brother’s orien­tation – has said in the past that Scott and his buddies have invited him out to gay bars but he “had to draw the line there.”

That made his surprise visit to the gay watering hole espe­cially meaningful.

“Scott was beyond thrilled when Chris decided to break his rule and showed up at Eleven shortly before mid­night,” said the source.

“Chris arrived with a beau­tiful blonde woman, but no one in the room was paying attention to her. And while it was Scott’s big night, Chris stole the show. Everyone in the area cheered him on when he chatted with some of the ‘man­kini’-wearing go-go boys, who were dancing on top of the bar.

“He even gave his stunning date money to stuff in their G-strings. Scott got a huge kick out of showing off his big brother to his pals. Chris was the hit of the party!”