The Philadelphia Phillies signed him to a contract in the hopes that a change of scenery would help him. Unfortunately, it was not to be. Blanton was a mere shadow of himself at this point in his career. Arm injuries and the fast life where taking their toll.
The best he could do with the Phillies was a 4-3 mark in his first season in 1940, followed by a miserable 6-13 in 1941. His 0-4 record in 1942 earned him a pink slip on June 12. Blanton tried to regain his old form with the PCL Hollywood Stars, going 9-9 in 1943 and 4-5 in 1944. But on March 27, 1945 he was suspended by the Hollywood Management for breaking training rules, having failed to get into shape since arriving at spring training.
By this time in life, Blanton's way had begun taking a toll on him. Amazingly, Cy got a letter from Uncle Sam, asking him to report for pre-induction tests. Of course he did not pass, and in fact was recommended by doctors to get more tests and treatment. Cy returned home to Oklahoma, where he was eventually admitted to the Central State Hospital in Norman on August 31. The painful end came on September 13, 1945, just 13 days after entering the hospital. He was just 37 years old.