Even before Strikeforce's first outing on Showtime has taken place, Frank Shamrock vs. Nick Diaz on April 11, the promotion's second Showtime card is close to being set.

Jake Shields will meet Robbie Lawler in the main event promotion's second Showtime event, as was announced at a press conference earlier this month. It now appears that the bout will likely take place in St. Louis on June 6. Lawler teammate Matt Hughes stated as much in his personal blog on Monday, which was also confirmed by other sources close to the fight who wished to remain anonymous, although the event's venue could not be verified.

When contact by MMAWeekly.com, Strikeforce officials could not confirm the date or location of the bout.

The fight is Shields' first as a middleweight, having competed as a welterweight throughout his professional career. The Cesar Gracie black belt was originally booked to fight Joe Riggs at "Shamrock vs. Diaz" on April 11, but believed a fight with former EliteXC middleweight champion Lawler would be a better move for his career. At the press conference for "Shamrock vs. Gracie," where the switch was first announced, Shields said he didn't expect to be at weight for the contest, but hoped to gain five to six pounds of muscle for the jump up.

Both Lawler and Shields have been inactive since the fall of EliteXC. Lawler's Strikeforce appearance will be his first in nearly a year, when he stopped Scott Smith with strikes in the second round of the CBS-televised "Unfinished Business" in July. The soft-spoken 27-year-old trains with Hughes at the H.I.T. Squad training center in Granite City, Ill.

The June card is also set to feature Renato "Babalu" Sobral, Rafael "Feijao" Cavalcante, Phil Baroni, Evangelista "Cyborg" Santos, Joey Villasenor and Kim Couture.

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