Finn is the Guelph Storm's captain and Brown wears the 'C' for the Erie Otters. Their teams open the best-of-seven series for the Wayne Gretzky Trophy in Guelph on Thursday.
"It's pretty cool for both of us to be playing against each other at this level and both be captains, and we're in the same National (Hockey) League organization as well," Finn said Tuesday on a conference call.
"We've both very competitive individuals and we both know that growing up with each other. It'll be a lot of fun playing against him."
The Oshawa Generals and North Bay Battalion will contest the Eastern Conference final for the Bobby Orr Trophy starting Friday in Oshawa.
The Maple Leafs chose Finn, a defenceman, with their 35th pick in the 2012. His buddy Brown, a right-winger, went four rounds later at No. 156 overall.
"Me and Matt had a conversation earlier in the week and we said that our friendship is going to take a hold here for a couple weeks while this series is going on," Brown said. "You get one shot at this. We're definitely not going to hold back on each other, that's for sure.
"It's going to be an interesting series and who knows? We might be matched up against each other and that should be even more fun."
Brown won the OHL's scoring title this season with 45 goals and 83 assists in 68 games.
"With Connor, it's always been about proving people wrong," Finn said. "He got passed over a lot in the OHL draft, a 13th-round pick, played a year of Junior A and finally made the lineup in Erie.
"To see him this year, put up the numbers that he did is crazy. I'm happy for him that it's worked out and he's had a great year but at the same time, it's going to be fun playing against him and hopefully beating him now."
Guelph was the best team in the OHL's regular season with 52 wins and 108 points. The Western Conference was tough with Guelph, Erie and the London Knights all finishing above 100 points.
The Knights host the MasterCard Memorial Cup in May. The Storm sent them to the post-season sidelines with a second-round win in five games.
The Otters rebounded dramatically after finishing far out of the playoffs the previous two seasons.
With the first overall pick in 2012, Erie gained Connor McDavid. He was only the third player to be granted exceptional status by Hockey Canada and be allowed to play in the league at 15.
Erie was well out of the post-season again last year, but equalled the Storm's 52 wins and finished just two points back of Guelph this spring.
"They're very proud of what they've done and they still want more," Otters head coach Kris Knoblauch said of his team. "Where they've come from last year has been a huge improvement, but if they don't win it all, they'll be disappointed."
Brown, McDavid and overage forward Dane Fox were among the OHL's top four scorers, but Guelph was actually the highest-scoring team in the OHL this season with 340 goals.
The Oshawa Generals finished first in the Eastern Conference with 90 points followed by North Bay with 82. The Generals took the most efficient route to the OHL's final four with sweeps in their first two playoff series.
Erie required nine games and Guelph 10, while the Battalion are the most battle-hardened semifinalist. North Bay went seven games against Niagara in the first round and six against Barrie in the second.
"There's advantages to finishing series earlier because you're well rested and not injured. There's advantages to go longer in series because it allows you deal with different types of adversity," Battalion head coach Stan Butler said.
"I don't think it's an advantage or a disadvantage."
The Battalion relocated to North Bay, Ont., last year after 15 seasons in Brampton, where attendance was lagging.
It meant the return of major junior hockey to North Bay, where the Centennials played for two decades before they were sold and moved to Saginaw, Mich., in 2002.
"People here have been really supportive of the team," Butler said. "All the games have been sold out. We weren't used to that in Brampton. There were a lot of games we played in Brampton where the other team had more fans at the game than we did. So it's a big difference for our players."
A Western Hockey League and Quebec Major Junior Hockey League champion will join the OHL champion and host Knights in the Canadian Hockey League championship tournament May 16-25.
The Kelowna Rockets, Portland Winterhawks and Edmonton Oil Kings are through to the WHL's semifinals. The Kootenay Ice and Medicine Hat Tigers require a Game 7 on Wednesday to determine which team meets the Oil Kings in the Eastern Conference final.
The Halifax Mooseheads and Val-d'Or Foreurs open their QMJHL semifinal series Friday, while the Baie-Comeau Drakker awaited the winner of the series between the Blainville-Boisbriand Armada and Rimouski Oceanic.