Making his first appearance on the NCAA Tournament stage this weekend, the Spartans’ first-ever Big Ten Freshman of the Year introduced himself to a national audience, with a breakout performance propelling the Spartans to the Sweet 16.

“Big heart, big heart, a lot of guts” MSU head coach Tom Izzo said of his freshman guard, leaning back in his chair and forming a heart with his hands across his chest.

“He’s a tough kid. He wants to play in the big games, the big stage. … Give our guys credit, they gave him some step-in 3-point shots. I mean, just about every shot he took was a great assist.”

Harris scored a career-high 23 points to help the No. 3 seed MSU men’s basketball team (27-8) take down No. 6 seed Memphis (31-5), winning 70-48 in the third round of the NCAA Tournament, Saturday afternoon.

With the win, Izzo reaches his 11th Sweet 16 and improves to 18-3 in the second game of an NCAA Tournament weekend.

Memphis came into the contest winners of 25 of their past 26, but the Spartans outrebounded the Tigers, 49-29, and forced Memphis into its worst scoring and shooting performance (29.7 percent) of the season.

“That team worried me as much as any team we played,” Izzo said of Memphis. “And the way it’s changed since 2000 is a high seed used to get you out of the first weekend. Now it barely gets you out of the first game, as we’re all seeing.

“But I thought our focus today was pretty good from the start. I really do.”

The game opened with senior center Derrick Nix following a miss on his first shot, grabbing the rebound and putting back a hook shot in the lane for the game’s first points.

Nix was one of three Spartans to score in double figures, finishing with 13 points and eight rebounds, teaming with junior center Adreian Payne, who added 14 points, 10 rebounds and a career-high five blocked shots.

MSU’s lead would last only momentarily, as the Tigers followed every MSU basket with a make of their own for the opening seven minutes.

That would change quickly as Harris caught fire and the Spartans went on a tear.

The freshman guard powered a 20-7 run, scoring 14 points, including four 3-pointers, to give MSU some separation, 26-13, with 7:59 to go in the first half.

“I mean, it always feels good to see shots going in,” Harris said. “I’ve just got to give credit to my teammates. They were able to find me when I was open and had confidence in me and I was able to knock down the shot.”

But Memphis had an answer, responding with a 12-2 rally, highlighted by back-to-back threes from guard Geron Johnson to pull them within three points, 28-25, with 3:06 remaining in the first half.

Consecutive baskets from Harris and freshman guard Denzel Valentine bumped the Spartans’ lead back up to seven points, before Memphis ended the half with four straight points of its own to cut the lead to 32-29 at halftime.

Using their advantage inside, MSU came out of the locker room strong, opening the second half with a 7-1 burst to extend its lead to nine points, with Nix scoring four early points.

But luck turned dramatically for the Spartans, as Harris picked up his fourth foul with 13:42 remaining, forcing him to the bench for an extended period of time.

MSU needed a player to turn to and, on this night, Harris wouldn’t be the only Spartan to put on a show.

With his team’s fate in doubt, Payne took over the game one play after another, bringing the crowd to its feet and putting the game out of reach.

From high-flying dunks to jaw-dropping blocked shots, the junior center’s complete arsenal of natural talent was on full display, outshining a Memphis team known for its athleticism.

“He was an X-factor,” Memphis head coach Josh Pastner said of Payne. “He’s a pro. There’s no question he’s a pro. … They’re going to the Final Four if he plays like that. I think he’s their whole key for them to get to the Final Four. If he plays like that, they’re hard to beat; very, very hard to beat.”

After Harris went to the bench, MSU rallied for a 15-7 run, with Payne scoring eight of the team’s 15 points, to move ahead, 54-39, with 7:51 remaining, all but sealing the victory for the Spartans.

After finishing with four points and three rebounds in the first half, Payne exploded for 10 points, seven rebounds and four blocked shots in the second half.

Yet the aspect of Payne’s performance Izzo might have been most proud of was his answer to a question about whether this team could celebrate reaching the Sweet 16 today or did all attention have to turn back to preparation with the final goal still not accomplished.

Payne said the team could enjoy the victory on the bus ride back to campus, but after that it would be back to business, preparing for the winner of the third round matchup between No. 2 seed Duke and No. 7 seed Creighton at 6:40 p.m., on Sunday.

The response drew an enthusiastic “A-OK” signal from Izzo and a chuckle from his star center.

“At halftime we had a little talk and I think that helped,” Izzo said. “He was very, very good. Better than even I thought he could be.

“What I’m trying to impress upon my team, because I do know what it takes to get there, is you have to have less mistakes, less mistakes, less mistakes, because you’re going to play better teams and better teams and better teams.”