DECATUR, GA -- We posted up at the quarterfinal round of the Region 6-AAAA tournament at Columbia High School on Monday. Games were good, competition was high and teams punched their tickets to the state playoffs.

Marist 59, Therrell 45

Marist senior guard Bobby Perez dove on the floor for loose balls, he hit a three-pointer, drilled a couple of midrange jumpers, found junior guard Cam Wiley for three three-pointers, collected five steals and rebounded in traffic against a bigger Therrell team.

"He's the toughest kid I've ever coached," said Marist head coach Greg McClaire.

That's not just coach speak after Perez played a big role in Marist's state playoff clinching 59-45 win over Therrell on Monday evening.

Perez is a tough guy. He's a brave guy, too. He's also a cancer survivor.

During the Christmas break he was going through his final round of chemotherapy to put away the disease that crept into his athletic teenage frame.

"I had my last treatment over the Christmas break and I'm getting my wind back. I think I'm back 100 percent," Perez said. "After that experience, I'm a little more grateful for this opportunity that God's given me. I'm trying to take advantage of it."

He did on Monday.

Perez shied away from any talk that praised his play or his courage, instead deflecting the compliments to Wiley and the rest of the War Eagles. Wiley scored a game-high 19 points in the win. The backcourt play was on point for Marist in this win.

"We are in that desperation mode so it is win or go home. We had to pick it up a notch. If you come out slow, it can be over," Perez said. "I've worked too hard to do that."

Stone Mountain 61, South Atlanta 51

There are some things in Georgia basketball that you just assume will happen. South Atlanta High School making the state tournament every year is one of them.

But in this 2013-2014 season, all assumptions are off. That's the kind of year it has been. That said, South Atlanta's season came to an abrupt halt on Monday night as Stone Mountain played the role of spoiler, putting the Hornets' season to bed with a 61-51 victory in the quarterfinals of the Region 6-AAAA tournament.

The Pirates turned up the defensive pressure in the second half and took control of the pace thanks to the calm and collected play of junior point guard Chris Jones and senior Damani Walker.

"We've been talking to our guys all year about how important defense is and they stepped it up on the defensive end, I thought, in the second half," Stone Mountain head coach Tony Stroud said. "We moved the ball well in the second half and set us up for good buckets."

Jones was the pilot to the Stone Mountain offense and methodically picked his spots to help direct the offense.

"He played excellent game. He set us up very nicely. He passed the ball inside to our big people and got us some big buckets late in the game," Stroud said.

Freshman Robert Sims scored 15 points and played very well on the big stage. South Atlanta's talented backcourt duo of Derrick Byrd and Costa Anderson struggled to find the offense in the second half, particularly in the third quarter.

Walker led Stone Mountain with 17 while Jones and Sims each pitched in with 15.

Grady 52, Lithonia 32

The winter weather didn't slow down Grady guard Tyrius Walker at all. The senior pumped in 20 first half points for the Knights and did it from all over the floor. Walker's offense helped Grady build a big enough to lead to cruise in a 52-32 win over Lithonia in the quarterfinals of the Region 6-AAAA tournament.

Walker hit from the foul line, at the rim, pull-up midrange jumpers and a couple of three-pointers. It was an impressive offensive showing to get things started. He finished with an efficient 22 points, five rebounds and five assists in the win.

The 5-foot-11 guard was named Region 6-AAAA Player of the Year. However, he's still a secret around the Atlanta hoops community. His coach echoes that opinion.

"He's the most underrated guard out there," Grady head coach Brian Weeden said.

Grady had little trouble putting away Lithonia and did it with simple defense. Weeden said he's looking to his team to step up more on the offensive end going into the semifinals of the region tournament.

"We had some mishaps in the early part but I was happy with our defense," Weeden said. "This time of year you have to execute on every play. You can't take anything off. We are going to have to readjust and do a better job of executing going forward."