John G "Jay" Grdina is an American businessman, pornographic actor, director, and producer who usually works with his former wife Jenna Jameson . He is often credited under the stage name Justin Sterling .

In 1992, he began investing in adult films directed by Michael Ninn .

From 1995 to 1999, he wrote and directed several films often under the name Michael Santangelo .

In 1998, Jay Grdina met Jenna Jameson. They married on June 22, 2003.

In 2000, Grdina and Jameson founded Club Jenna Inc. , which began as an Internet Pornography company.

He produced, directed, and wrote best-selling and adult industry award winning Club Jenna films including, Brianna Loves Jenna , The Masseuse , I Dream of Jenna , and Krystal Method . He also acted in many of these films, as the only man that Jenna Jameson would have intercourse with onscreen. He won the 2005 AVN Award for Best Actor for his role in The Masseuse, using the stage name Justin Sterling.

In 2004, Details magazine named him as one of the 10 most successful men under the age of 37 in America.

On June 22, 2006, Playboy Enterprises announced the acquisition of Club Jenna in conjuction with personal agreements by both Jameson and Grdina.

For the 2006 second season of Playboy TV’s Jenna’s America Sex Star , he participated as the show’s judge.

On August 2006, Jenna Jameson’s publicist confirmed the famous porn star couple’s separation where they filed for divorce on December 12, 2006.