The UFC on FX 2: "Alves vs. Kampann" weigh-in event took place last night (Thurs., March 1, 2012) in Australia and that means staredown pics from all the major players.

That includes the two headliners for tomorrow night's event at the Allphones Arena, Thiago Alves vs. Martin Kampmann. The notoriously beefy "Pitbull" came in right at the 170-pound limit, making this potentially explosive match-up official.

The first ever UFC flyweight tournament is also official, as all four men competing tomorrow night, Demetrious Johnson vs. Ian McCall and Joseph Benavidez vs. Yasuhiro Urushitani, hit their mark at 125.5-pounds. Check out their staredown pics -- along with the final main card middleweight bout pitting Court McGee vs. Constantinos Philippou -- after the jump.

For complete UFC on FX 2 weigh-in results click here.