Early on in his NHL career with the New Jersey Devils, Clarkson made a habit of bugging the New York Rangers star winger. Over time his role changed.
"He used to be more of an agitator," Gaborik said. "He kind of became more of a guy that can score goals and just play hard in tough games."
Clarkson made his Toronto Maple Leafs debut Friday night against a seemingly unknown opponent, but it was clear Gaborik and many of his Columbus Blue Jackets teammates were plenty familiar with the changes in the power forward's game.
"It's interesting to see how he's evolved as a player," said forward R.J. Umberger, who played against Clarkson a lot during his time with the Philadelphia Flyers. "I remember early in my career he was a big agitator, he was one of those pesty type of guys that you had to get under his skin, you had to watch out for, make sure he didn't do anything dirty.
"He's developed into a great scorer."
Along with Umberger and Gaborik, Nick Foligno (Ottawa Senators), Blake Comeau (New York Islanders) and Mark Letestu (Pittsburgh Penguins) had some battles against him during their time in the Eastern Conference, and of course Brandon Dubinsky and Artem Anisimov saw plenty of him during the Rangers-Devils rivalry.
Clarkson had 12 points and 79 penalty minutes in 33 career regular-season games against the Rangers, so it's no wonder Gaborik has such memories about him.
"I fought my way into the league, if you look at my fighting majors or what I did to get into the league," Clarkson said. "Definitely when I was younger there was more fighting or agitating, but I still don't shy away from that now."
Clarkson had 20 fights in his first full NHL season, 21 in his second and hasn't gotten close since. Still, Foligno said it's easy to notice him when he's on the ice.
"He's a guy that battles, goes to the nets," Umberger said. "He's gritty, tough, obviously can fight. In the past few years his goal-scoring has really took off. He's just one of those two-way, complete players."
That didn't happen immediately. Clarkson was a spotty offensive player until a breakout, 30-goal season in 2011-12.
The 29-year-old Toronto native had to work at it over time, especially over the summer. But Gaborik also pointed to New Jersey's system as something that likely helped Clarkson's development as he started getting more power-play time alongside Zach Parise and others.
"You always try to play that game where you're responsible in your own end, can play in the other end and that's something that playing the Devils' system you have to be good at or you have to pick up on somewhat along the way," Clarkson said. "That's part of what they've taught me there."
Clarkson still wants to maintain an edge to his game, something that was clear when he was handed a 10-game suspension for leaving the bench to come to teammate Phil Kessel's aid against the Buffalo Sabres' John Scott during the now-infamous pre-season brawl.
Blue Jackets coach Todd Richards believes Clarkson brings much more between the whistles, notable grit and toughness.
"He's really good out front of the net," Richards said. "He goes to the net hard, but he plays there and he does a good job providing screening, deflections, and he might occupy two defenders to him, which will open up somebody else. He does that extremely well."
That worked so well in New Jersey that Clarkson managed to cash in on a US$36.75-million, seven-year deal with the Leafs in the off-season. Now in the East, the Blue Jackets will see the new, more mature Clarkson twice more this season.
"We'll see how that's going to go for him in Toronto," Gaborik said.