Middleweights Joe Riggs (28-10) and Kazuo Misaki (20-8-2) will collide in a middleweight tilt when Strikeforce returns to the Playboy Mansion in Beverly Hills, Calif., on September 20.

Misaki -– the Pride FC 2006 Welterweight Middleweight Grand Prix winner -– is on a two fight win streak and has been victorious in five of his last seven appearances. The "Grabaka Hitman" has taken on the world’s best at 185 pounds throughout his career, including Dan Henderson, Yoshihiro Akiyama, Denis Kang, Paulo Filho, Frank Trigg, Nathan Marquardt, Ricardo Almeida and others.

He is a tremendous talent and was a big-time acquisition for San Jose-based mixed martial arts promotion. And Misaki is eager to show his new employer that the company made a wise choice.

Here’s a snip from a recent press release:

"I am looking forward to making my debut for Strikeforce at The Playboy Mansion, an incredible venue that is well-known throughout the world…. Joe Riggs is a tremendous competitor. His style is aggressive like mine so I have no doubt that our fight will be an exciting and memorable one."

Riggs –- who has been plagued by injuries and other issues outside the cage throughout his career –- will compete in the middleweight division one final time before settling once and for all in the welterweight division. The talented 25-year-old Arizona native has had an up-and-down career and there’s no doubt that a win over Misaki would be a huge lift.

"Diesel" most recently defeated Matt Dempsey via submission (rear naked choke) Rage in the Cage (RITC) 112 back in July, marking a successful return from his most recent back injury that cost him a possible win against Corey Devella at Strikeforce: "Strikeforce At The Dome" earlier this year.

Here’s a snip from Riggs:

"The back’s great. It’s 100 percent. I’m really excited to be healthy again and looking forward to getting back on top."

According to the press release, the showdown between Misaki and Riggs is the first confirmed "Strikeforce At The Mansion II" match up. The lineup will eventually comprise 10 bouts and likely feature lightweight champion Josh Thomson in the main event of the evening.

Stay tuned for more fight card updates.