#52 is surprisingly thin. Let's go.
5. Brian Reith (-0.6 WAR)
Reith had two stints with the Reds, one where he was a starter in 2001, and a second stint from 2003 to 2004 where he wore #52. He was a reliever in his second go-round, making 42 appearances with a 4.11 ERA in 2003. Absolutely serviceable. He had an ERA over 7 in '04, and ended up in the minors in the Pirates organization before washing out to Indy ball shortly after.
4. Ricky Stone (-0.6 WAR)
Ricky Stone is an interesting cat, to me. He's a local boy, first off, who grew up a Reds fan in Hamilton. He was a solid reliever in the Astros system for a long time, and moved to his home team in 2005. Injuries plagued his time here, which could have led to him showing up on the Mitchell Report for steroid use. After a year in China after washing out with the Reds, he suffered a grand mal seizure at his home and barely survived. They found a brain tumor after that, and he's now (reportedly) better, and still living in the area. Good for Ricky.
3. Danny Ray Herrera (0.2 WAR)
He might not have been the best Red, but he was one of Red Reporter's favorite sons. What's not to like? To call him diminutive was an understatement, and he was a lefty who threw a screwball. For a year or two, he was a really good pitcher as well. 2009 was his best season with the Reds, appearing in 70 games for a 3.06 ERA. Since then, he was selected off of waivers by Milwaukee and was traded to New York in a deal for a pretty major player. (Trivia for today: who was he traded for?) 2011 was his last year in the big leagues, and he spent last season playing with Ben Broussard, Bill Hall, Ian Snell, and another former Red in Dontrelle Willis on the Long Island Ducks.
2. John Franco (2.0 WAR)
Our "rookie with a high number" is pretty high up on today's list. Franco wore #52 in 1984, where he appeared in 54 games as a 23-year-old. He put up a 2.61 ERA, which was pretty solid for a rookie. Even though he spent the bulk of his career with the Mets, he'll be on another one of these lists.
1. Tony Cingrani (2.4 WAR)
The Cinnerman has been THAT good since he's been up. His 2.92 ERA in his 18 starts last year earns him more value than Franco, and is equivalent to the value of everyone else on this list put together. It looks like he'll get a full shot in the rotation this year, so hopefully he can take advantage of it.