A U.S. appeals court lifted the stay of execution for a Missouri inmate who is scheduled to be executed Wednesday night.

The 8th U.S. Circuit Court of Appeals ruled that the state may go ahead with the execution a day after a federal judge ruled otherwise as convicted murderer John Middleton's lawyers do everything they can to halt the execution, Reuters reports.

Though the appellate court refused a secondary request by the 54-year-old's defense team to go before the whole court, they did open the door for the lawyers to file for a rehearing.

With options dwindling, they also turned to the state's highest court for a stay, while also filing for a hearing to determine whether or not Middleton is mentally competent to be executed.

U.S. District Judge Catherine Perry ruled in their favor Tuesday evening, saying there appeared to be a chance their claims of Middleton being mentally incompetent were legitimate.

A psychiatrist who examined the former meth dealer on death row for three murders said that he "lacks a rational understanding of the reason for the execution and is therefore not competent." Other inmates have signed affidavits claiming he is known to talk "to people who are not there, and tells stories that could not have any basis in reality."

In addition to fighting to find Middleton mentally incompetent, as he is a former methamphetamine user, his defense team have claimed that he is actually innocent of the murders and that it was other drug dealers acting out of revenge towards three snitches.