DAYTON, Ohio — Terrence Williams wouldn't let top-seeded Louisville crumble under pressure.

The carefree forward known to skip and dance across the court got serious after the Cardinals fell behind in the second half today, rallying his top-seeded team to a 79-72 victory over Siena in the second round of the NCAA tournament.

The carefree forward known to skip and dance across the court got serious after the Cardinals fell behind in the second half Sunday, rallying his top-seeded team to a 79-72 victory over Siena in the second round of the NCAA tournament.

Louisville (30-5) advanced to the round of 16 for the second straight year. The Cardinals will play 12th-seeded Arizona in the Midwest Regional on Friday in Indianapolis.

Siena (27-8) overcame a 12-point deficit in the second half and led by four before Williams took over, hitting 3s, getting rebounds and starting fast breaks with one-handed passes. He finished with 24 points and 15 rebounds.

Edwin Ubiles scored 24 points for the Saints, who handled Louisville's full-court pressure and then applied some of their own. The Cardinals headed to the bench for a timeout with stunned expressions after Clarence Jackson's lay-in put Siena up 63-59 with 7:20 to go.

Williams took it from there.

The senior forward who was so cool under pressure that he skipped across the court during pregame introductions drove for a basket and hit a 3-pointer that changed the momentum. He had nine points, five rebounds, a steal and two one-handed passes for layups down the stretch.

Louisville had won its last 11 games and the Big East regular-season and tournament titles by applying the pressure — full-court, nonstop. The Saints handled it without much problem — only nine turnovers — and applied a little of their own in the second half, making it a game.

They had no answer for Williams.

His two free throws with 35 seconds left put Louisville ahead 76-69 and ended the Saints' upset chances. The loss extended the Metro Atlantic Athletic Conference's history of never having a team reach the round of 16.