The main card of UFC 146 in Las Vegas is finally underway on Saturday night. The pay-per-view, which features five heavyweight bouts, will be capped off with a main event title fight between Junior dos Santos and Frank Mir.In the first fight on the main card, Lavar Johnson took on Stefan Struve. Johnson fights out of San Jose and was coming into his third UFC fight with two straight Knockout of the Night honors. He knew he would be facing a dangerous grappler and would need to keep the fight upright.In the first round, Johnson got Struve to the ground and attempted to land some shots to the downed Struve while standing. Unfortunately, Struve’s tremendous wrestling paid off, as he grabbed Johnson in a nasty-looking armbar and flipped over, forcing Johnson to tap at just 1:05 into the fight.With the loss, Johnson now holds a record of 17-6.For more on mixed martial arts in general, check out everything we have to offer over at MMA Fighting and Bloody Elbow.