The official weigh-in event for Strikeforce Challengers 18 took place today (Aug. 11, 2011) in the Key West Ballroom of Las Vegas' Palms Casino Resort. It was the last pre-fight event before tomorrow night's card, which airs live on Showtime at 11 p.m. ET in Las Vegas, Nevada.

The main event will see Ultimate Fighting Championship (UFC) veteran Jorge Gurgel enter into the hexagon against fellow lightweight contender Joe Duarte. Gurgel looks to halt Duarte's current four-fight win streak in a pairing that could produce some late summer fireworks.

Also on the card is an exciting match-up between top middleweight contender Danillo Villefort and Bellator Fighting Championships veteran Nate James. Villefort will look to circle the "Welcome Wagons" and make James' Strikeforce debut an unsuccessful one. 

Check out the Challengers 18: "Gurgel vs. Duarte" weigh in results below.

Main Card

155 lbs.: Jorge Gurgel (154) vs. Joe Duarte (155)
185 lbs.: Nate James (185) vs. Danillo Villefort (186) 
155 lbs.: Pat Healy (155) vs. Eric Wisely (156)
145 lbs.: Sarah D'Alelio (146) vs. Ronda Rousey (146) 
205 lbs.: Roy Jones (204) vs. Derrick Mehmen (205)

Preliminary card

205 lbs.: Keith Berry (204) vs. Gian Villante (205)
170 lbs.: Nah-Shon Burrell (171)* vs. Lukasz Les (169)
170 lbs.: Mike Bronzoulis (169) vs. Chad Leonhardt (171)
155 lbs.: Milton Vieira (155) vs. Sterling Ford (156) 

*Burrell originally weighed in at 172 pounds and was given two hours to cut the required one pound. He was able to do so.*

Remember MMAMania.com will provide LIVE blow-by-blow, round-by-round coverage of "Gurgel vs. Duarte" beginning with the Showtime telecast starting at 11 p.m. ET.

It's going to be a great night of fights so don't miss out, and remember to check us out for all the post-fight coverage after tomorrow night's card is wrapped up.