KANSAS CITY, Mo. -- Hopefully someone taped Bill Self's halftime speech. He might want to use it again.
Top-seeded Kansas (31-5) outscored North Carolina 49-28 in the second half to defeat No. 8-seeded North Carolina 70-58 in the third round of the NCAA Tournament on Sunday at Sprint Center.
Kansas advanced to the Sweet 16 and will play Michigan Friday in the South Regional semifinals.
Self said his team "played miserably" in the first half, but the Jayhawks stormed out the gate in the second half behind Travis Releford.
"I told them, 'If we just keep doing what we're doing, we'll be fine,'" Self said, tongue in-cheek. "I wasn't happy with them. It's OK not to play your best, but at least don't play your best when you're being yourself. We weren't ourselves at all in the first half. We had to have some individuals step up. Travis was terrific."
Releford scored 12 points in the first 8:24 of the second half to help Kansas turn a nine-point halftime deficit into a nine-point lead.
"The first half we just let those guys get whatever they wanted," Releford said. "The key in the second half was we got out and defended them a lot better."
Releford finished with 22 points, including 13 in the second half, to lead the Jayhawks. Jeff Withey added 16 points and 16 rebounds for Kansas. He also blocked five shots. Withey now stands second to Tim Duncan (50) of Wake Forest in blocks in NCAA tournament history with 43.
"Hopefully we can keep on winning games so I can keep on blocking shots," Withey said. "Hopefully I can pass (Duncan)."
Withey contributed to Kansas' domination on the glass, as the Jayhawks outrebounded the Tar Heels 21-12 in the second half, and 50-36 overall.
"In the first half, I thought (the team's approach to attacking Withey) was pretty good," North Carolina coach Roy Williams said. "In the second half, it wasn't nearly as effective."
P.J. Hairston had 15 points and James Michael McAdoo had 11 for North Carolina, which finished the season 25-11.
The Jayhawks started the second half on a run that lasted well past the midway point of the half. Releford, the only Jayhawk with more than one made field goal in the first 23 minutes of the game, had a put-back and a 3-point field goal to begin the surge. He later followed another Kansas miss with a basket to cut the lead to 33-32. When he tipped in a Ben McLemore miss at the 14:36 mark, Kansas had regained the lead at 37-35.
"The second half we didn't quite have the same energy," Williams said. "They got into rhythm, started making shots, and we couldn't stop them.
"I think their defense fed off that. When the ball started going in the basket, I thought their defense got even stronger."
Both teams started cold, with the Jayhawks hitting just one of their first 13 shots. North Carolina was only slightly better, going 4-of-17. But two of those were 3-pointers as the Tar Heels grabbed a 12-2 lead. Kansas stormed back with a 13-2 run of its own to grab its first lead.
But the Tar Heels pulled away late in the half to lead 30-21. North Carolina finished the first half shooting only 26 percent. Kansas was at 25 percent. It was the worst shooting half in Kansas' NCAA Tournament history.
Withey didn't contribute much on the offensive end early in the first half, but he certainly made his presence felt on the defensive end. He had nine rebounds and two blocks, plus he altered a number of shots in the first half.
NOTES: This was the second year in a row, and third time in six years, that these two teams matched up in the NCAA Tournament. Kansas has won all three meetings, including an 80-67 victory in the Midwest Regional Final last season. Kansas also defeated North Carolina 84-66 in the Final Four in 2008 when Kansas won its last national championship...North Carolina's Williams won his 700th game Friday against Villanova, becoming the third-fastest to reach that total (879 games) behind Adolph Rupp (836) and Jerry Tarkanian (876). Of his 700 wins, 418 came as head coach of Kansas (1988-2003)...These two schools rank second (Kansas, 2,101) and third (North Carolina, 2,090) in all-time NCAA Division I wins behind Kentucky (2,111)...Kansas is the only school to win 31 or more games in four straight seasons.