This is the Strikeforce live blog for Josh Barnett vs. Nandor Guelmino, a heavyweight bout during Saturday night's Marquardt vs. Saffiedine event at the Chesapeake Energy Arena in Oklahoma City, Okla.

Barnett, who has won four of his past five fights, will face Guelmino, who is making his Strikeforce debut, on the main card.

Check out the Strikeforce live blog below.

Round 1: Kevin Nix is our referee. Barnett immediately shoots in and muscles Guelmino to the canvas. Barnett working from inside Guelmino's guard, postures up and jumps on a leglock. Guelmino escapes then defends a trip attempt, but gives up his back in the process. Barnett looks for the trip again, and this time he gets it. Barnett lands on top in mount and almost instantly sinks in an arm triangle choke. Well, that was quick.

Josh Barnett def. Nandor Guelmino via submission (arm triangle choke) at 2:11 of round 1.