"Sherron (Collins) made some good plays," said Rush, who made one of his last appearances before his hometown fans. "Everybody down the stretch made some good plays for us. Russell (Robinson) made a good play at the end and put us up four. That won the game for us. Everything was just falling for me."
The two-time defending champion Jayhawks (30-3) will meet No. 6 Texas for the championship for the third year in a row. Kansas and Texas tied for the regular-season title, but the Longhorns bested the Jayhawks 72-69 in their only meeting.
The Aggies (24-10) outrebounded Kansas 35-25 and hit almost 54 percent of their shots but couldn't stop Rush, who would be in the NBA today if a knee injury sustained in a pickup game in May hadn't forced him back to college.
Rush did admit he felt an extra spurt of adrenaline playing just a few blocks from where he grew up.
"It made it real special, just because I'm back home," he said. "I played terrible yesterday. I wanted to come out and show everybody what I could do."
Texas A&M's Donald Sloan hurt his ankle in the first half and wound up playing only 12 minutes. The sophomore guard, who had 12 points, nine rebounds and nine assists in the opening-round victory over Iowa State on Thursday, left immediately for his home in Dallas. Services are pending for his mother, who died Thursday following a lengthy illness.
"At halftime, he said he was done," coach Mark Turgeon said. "And then he looked at me when they made that run and he said, 'Coach, I want to play,' and obviously he wasn't ready."
Rush grabbed a defensive rebound and Darnell Jackson converted it into a 72-66 lead with less than 3 minutes left, then Jackson increased the lead with a free throw.
But back came the Aggies, quickly slicing the lead to 73-71 on Beau Muhlbach's 3-pointer and a pair of free throws by Dominique Kirk with 54 seconds to go.
Robinson, one of four guards who powered Kansas to its fourth straight regular-season Big 12 title, dribbled around Texas A&M's packed-in defense for a one-handed layup.
"We were just trying to hustle, and we just miscommunicated at the last minute and he just made a layup," Kirk said. "You can't dwell on that."
Muhlbach then missed a 3-pointer and Josh Carter's tip-in clanged off the rim. Mario Chalmers grabbed the rebound for Kansas, which beat the Aggies 72-55 in the regular-season finale.
"They just made great shots at the end of the game, and we didn't get the defensive stop that we needed," Kirk said.
With 6 seconds left, Rush was fouled and made both free throws, triggering a huge roar from the pro-Kansas crowd the Jayhawks always enjoy in Kansas City.
"I thought it was a fabulous college basketball game," Kansas coach Bill Self said. "I thought there was some high-level stuff going on out there, especially in the last 10 minutes."
Jackson had 14 points for Kansas and Collins added nine. Bryan Davis had 16 points and Joseph Jones 14 for Texas A&M, which will hope to be at least the fifth Big 12 team to get an at-large bid to the NCAA tournament Sunday.
"It's going to be pretty anxious," Kirk said. "We just want to see where we're going, and hopefully we can take it from there. As long as we keep competing like we did today, I think we'll be fine. I think we did enough, but we'll see."
The Aggies closed out the first half on an 8-0 run, forging a 34-34 tie, with Jones getting three points and Kirk making a long 3-pointer and following that with another a basket.
Kansas quickly went back on top after intermission. Rush's tightly contested 5-footer went in at the 9:21 mark for a 57-49 lead. Then the teams traded 3-pointers, with four going down in a span of 1 minute, 9 seconds starting with Bryan Davis' over-the-shoulder heave that somehow banked in at the buzzer.
"I just threw up a prayer and hoped it went in," Davis said.
Rush came right down court and answered with a 3 from the top of the key, then Carter canned a long one for the Aggies and Collins again answered for the Jayhawks after taking a nifty pass from Chalmers, making it 63-55.