Auburn’s Tahaad Pettiford and Michigan State’s Jase Richardson are high-scoring, left-handed freshman guards who have more in common than big games that helped to propel their teams to the NCAA Tournament’s Elite Eight.

The guards also share a rivalry that includes on-court matchups long before either began his college career. Even though Pettiford is from Jersey City, New Jersey, and Richardson, the son of former Warriors star Jason Richardson, is from Denver, they already have a history of playing against each other as rising top talents on the AAU circuit.

Today, the rivalry between the freshmen will rise to a new level when No. 1 seed Auburn faces No. 2 seed Michigan State in the final game of the South Region with a Final Four spot on the line.

“When you get to play guys you’ve grown up with and play in AAU circuits and camps, it’s super fun,” Richardson said Saturday. “You get to play them at the highest level. So just to have that matchup in the Elite Eight is special.”

Each freshman played lead roles in his team’s second-half rally for Sweet 16 wins on Friday night.

Pettiford scored 15 of his 20 points in the second half to help Auburn erase a second-half deficit in its 78-65 win over Michigan.

Richardson and the Spartans (30-6) trailed by 10 points in the first half and nine points after halftime before charging back for a 73-70 win over Mississippi. Richardson was efficient, making 6 of 8 shots, including 4 of 6 3s, and scored 10 of his 20 points in the second half.

Houston edges Purdue to advance >> Milos Uzan soared for an uncontested layup on a beautifully executed inbound play with 0.9 seconds left, and No. 1 seed Houston survived a late collapse to beat fourth-seeded Purdue 62-60 on Friday night in the Sweet 16 in Indianapolis.

Houston led 56-46 with just under eight minutes remaining but made only one field goal from there until Uzan’s tiebreaking bucket. He inbounded the ball from the baseline to Joseph Tugler, who threw a bounce pass back to Uzan, and the 6-foot-4 junior took it to the rim.

Coach Kelvin Sampson’s Cougars (33-4) advanced to the Elite Eight for the third time in five years after falling in the Sweet 16 as a top seed in the previous two editions of March Madness. They’ll take the nation’s longest winning streak, 16 games, into today’s Midwest Region final against No. 2 seed Tennessee.

Houston, the Big 12 regular-season and tournament champion, became the fourth No. 1 seed to reach the Elite Eight. The Cougars haven’t lost since Feb. 1.