Not necessarily a closer, but another late inning bullpenner could help in light of Madson's injury.
Reds could trade Bailey, Francisco, Frazier, Janish, Francis, Heisey, or prospects. No need to deal from the core.
Relievers aren't popular around here, unclear to me anyone would want to do this.
Also, Reds do have some bullpen depth so a trade isn't essential.
But one more late innings veteran might help and the Reds certainly have the trading chips.