‘Spider’ steps up in class

Anderson Silva’s recent sluggish performances have been attributed to a lack of competition from the top contenders in the middleweight division.

Perhaps Silva will find the motivation to return to top form when he steps up to fight one of the best light heavyweights in the world.

The Ultimate Fighting Championship announced Tuesday that Silva will meet Forrest Griffin in a nontitle bout in the co-main event of the organization’s first card in Pennsylvania on Aug. 8.

The fight will share top billing at the Wachovia Center in Philadelphia with BJ Penn defending his lightweight crown against Kenny Florian.

Silva, a winner in a UFC-record nine straight fights, previously moved up to 205 pounds to rout James Irvin in July. But Griffin represents a significant upgrade in competition for “The Spider.”

Griffin, a Las Vegan, is a former light heavyweight champion. A victory over Silva, widely considered among the best pound-for-pound fighters, could propel him back into contention for the belt that he lost to Rashad Evans in December.

Florian has been the top contender for some time but had to wait out Penn’s foray into the welterweight division, where he lost to Georges St. Pierre.

• STRIKEFORCE UPDATE — Strikeforce will host just its third show outside California when it ventures to St. Louis on June 6.

The upstart organization will look to capitalize on its successful April 11 show in San Jose, Calif., as several of the same fighters return to action.

Scott Smith and Nick Diaz, each winners in San Jose, will square off at a catch weight of 180 pounds.

Diaz dominated Frank Shamrock in the April 11 main event. He said he plans on doing the same thing against Smith.

“I really hate that (Smith) brings his kids to every one of his fights because now I’m going to be made out to be the bad guy or some sort of villain after I beat him up,” Diaz said in a statement.

Smith also fought on that card, winning by third-round knockout over Benji Radach.

The card, which will air live on Showtime, will be headlined by another catch-weight bout: Jake Shields vs. Robbie Lawler at 182.

Kim Couture, the wife of former UFC heavyweight champion Randy Couture, also will appear on a Strikeforce card on Showtime when she takes on Meisha Tate on May 15 in Fresno, Calif.

Contact reporter Adam Hill at ahill@reviewjournal.com or 702-224-5509.