The NCAA tweaked its rules this season to give offensive teams more of an advantage.

The Final Four this weekend in Texas will feature teams sharing a common thread: Lockdown defenses.

Florida has been one of the nation's best defensive teams all season and Wisconsin has been near the top ever since Bo Ryan took over in Madison a dozen years ago. Kentucky's high-flying freshmen are among the best at swatting shots and UConn never gives an inch, even against bigger opponents.

Louisville won last year's national title with its chaos-inducing defense, Kentucky took the title in 2012 behind shot-swatting freshman Anthony Davis and UConn held Butler to 41 points in the 2011 title game.