He first attended Purnell's Clemson camp as a seventh grader. When Sullivan was back for a second camp stay a year later, he was already on the radar as a prospect in the 2011 class.
Purnell fostered a strong bond over the next three years, and it was no secret that Sullivan had become a heavy Clemson lean. In fact, a verbal commitment to the Tigers was imminent.
Then, things turned on a dime in the spring of 2010.
Purnell left Clemson for DePaul while Sullivan was a junior, and he was just as surprised as everyone else.
"Honestly, it was kind of tough," Sullivan said. "I remember waking up and seeing on SportsCenter. I was like, ‘Wow.' I was probably on the phone with him a week [before]. It definitely throws you off, because that was my coach right there."
In from Wright State came Brad Brownell. Just as quickly as things turned for the worse, they got better.
"The [new] coaching staff hit me right back within the next two days," Sullivan said. "Honestly, the coaching staff right now isn't that much different. It didn't change.
"Really, I like it a lot better."
By late August, Brownell had his first commitment as Clemson's head coach.
"There's a reason why I started so early. And there's a reason why they stayed with me. Just that showed me this was the place I was supposed to be," Sullivan said.
A successful year one under Brownell showed Sullivan that he had indeed made the right choice. Clemson finished 22-12 (9-7 ACC) and won their first-round NCAA Tournament game against UAB.
"That's amazing right there that he can come in--brand new--and still get the guys to play as hard as they can, in spite of some guys transferring," Sullivan said. "That definitely showed me that this is the coach I wanted to play for."
And Sullivan is the kind of player Brownell wants playing for him.
The No. 17 power forward in the class of 2011, Sullivan averaged 15.6 points and 7.4 rebounds during his senior season at Davidson Day School in Charlotte, N.C.
His four-star rating by Scout.com was the highest in Brownell's five-man class.
"It's pretty much a whole new playing field, coming here. I'm fairly sure the coaches forget that," Sullivan said. "It's freshmen and everyone else on the team.
"Just because I'm a highly ranked player, it doesn't mean I can't work as hard as I can and expect something. For me, it's like a new start, really."
Now, what's important is developing into a player that Brownell will come to rely on over the next four years.
A 6-foot-7, 225-pound lefty, Sullivan likens his game to another slightly undersized big who Purnell relied on during his stay at Clemson.
"Honestly, it's probably [comparable] to Trevor [Booker]," Sullivan said. "Not the tallest big man, but athletic and physical. Then, can also step outside and knock down jumpers--can take a couple a couple of dribbles and get to the basket. So, probably Trevor."
So Brownell already has the next Booker, huh?
Hope springs eternal in the month of July.
The Clemson men's basketball program announced the signing of a pair of prospects to national…