Unofficially, Oscar Robertson and Magic Johnson are the only other players to post at least two triple-doubles in the tournament (assists weren't officially counted until 1984).

"He's just got a motor," Saint Louis' Brian Conklin said of Green.

Keith Appling netted 19 points, while Brandon Wood and Derrick Nix each added 10 points for the top-seeded Spartans (29-7), who have reached the regional semifinals in three of the past four years.

The Spartans will face fourth-seeded Louisville in a West Region semifinal in Phoenix on Thursday after a tough test from the ninth-seeded Billikens.

Michigan State coach Tom Izzo said he knew it would be tight, especially since Saint Louis is coached by Rick Majerus.

"I don't know if you would believe this or not, but I thought to myself the game would go just like it went," said Izzo. "I didn't know who would win, but I told my guys I know what good a coach he is.

"I knew it would be a physical war. We play in the Big Ten, and I thought it was a physical game. And I thought we had our chances."

Kwamain Mitchell had 13 points and Conklin added 11 for Saint Louis (26-8), which has never been to the Sweet 16.

Appling's back-door layup with 11:42 remaining gave Michigan State its largest lead of the contest, 45-34, but led by Mitchell, the Billikens didn't go down quietly.

Mitchell nailed a pair of three-pointers and assisted on two other baskets during a 12-4 Billikens run to pull them within 49-46 with 5:34 left.

A bit later, Mitchell's layup cut the deficit to 53-51 with 3:19 remaining, but the Billikens never got any closer as the senior Green took over.

He knocked down a pull-up jumper that made it 55-51. After Cory Remekun missed a layup at the other end, Green drove and kicked to Appling on the right wing. Appling's triple rolled around the rim for an eternity before finally falling through the hoop for a 58-51 advantage with 1:34 to play.

The Spartans then made 6-of-8 foul shots before Mike McCall Jr.'s trey trimmed the margin to 64-61 with 10 seconds left.

But Thornton knocked down 1-of-2 from the stripe to seal the win for the Spartans.

Michigan State shot 61.9 percent in the second half.

"We fought our guts out (but) they're a terrific team," said Majerus. "I don't know that we could have played better."

Despite shooting just 23.8 percent in the opening 20 minutes, Saint Louis found itself down by just five, 26-21, entering the break. The Billikens hung around by going 9-of-13 from the line and forcing nine Michigan State turnovers.

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