"You're still doing your thing and you're still trying to pitch, it's that added little friendship that's involved with the game is kind of cool," Leake said on Thursday.
The pairing wasn't lost on Reds manager Bryan Price, who was Arroyo's pitching coach the past four years. Both pitchers lack power velocity, but have been successful with deception, location and craftiness.
"It's an interesting coincidence that they would be matched up against each other for sure," Price said. "I think Bronson had a really positive influence on many of our pitchers, no one more than Mike. In many ways, it was how to embrace the competition and how to have fun and really enjoy your time at the ballpark and embrace the work. I would put Mike Leake and Bronson in that upper echelon of hard work and preparation guys I've had as well."
Arroyo, who was not brought back over the winter and signed as a free agent with Arizona in February, was one of Cincinnati's most popular pitchers from 2006-13. During his eight seasons in a Reds uniform, Arroyo went 105-94 with a 4.05 ERA. He had seven 200-inning seasons and the one he missed in 2011 saw him pitch 199 innings. There were five seasons in which he had at least 14 victories, including 17 wins in 2010.
"It's a bizarre situation, because this is the first time I will pitch against an entire team that almost every guy came up as a rookie when I was already an established Major League player," Arroyo said. "I dressed these guys in diapers. It's weird, it's like pitching against your best friend that's lived next door to you your whole life for the first time -- not just Leake, but everybody."
Arroyo expects a unique chess match against a Reds team that knows his entire bag of tricks on the mound.
"These guys know my game as good as anybody," Arroyo said. "Bryan Price, I've probably been as intimate with him as anybody I've ever been with in the game about my pitching style and my selection and why I do things. He's heard me talk about my idea of how to beat hitters and my theory on it for a very long time."
Arroyo and Leake have spoken already about facing each other.
"I talked to him today," Leake said. "He's always been a little jokester, so he asked me if I was ready for the face off. He's a good guy and I like him a lot."
Leake has pitched very well this season, with a 2.79 ERA in 10 starts, but has a 2-4 record because of poor run support. He is 0-2 with a 1.77 ERA in five starts this month.
Arroyo, who is 4-3 with a 4.15 ERA in 10 starts while also dealing with injuries, had a tough time predicting how Friday might turn out for him.
"I'm either going to put all zeros on the board, or I'm going to put up a nine spot," he said. "I don't think it's going to be anything in between."