Allen Johnson is racing this weekend at the NHRA AAA Midwest Nationals with part of his mind on the task at hand and the other worrying about his father and engine builder Roy Johnson back in Knoxville, Tenn.

The elder Johnson underwent surgery last week week to correct a lower back issue described as three alignment problems. Allen confirmed there was a fusion process and a cage put around the surgically repaired area. Unfortunately, the healing process has not gone as well as doctors or his son had hoped.

"He started experiencing some pain in his legs after the surgery," Allen explained. "We took him back to local Emergency Room and they did an MRI on him. They saw something they didn't like and had him transported back to Knoxville last night."

According to Allen, doctors performed surgery and removed "a rather large hematoma."

Allen said the hematoma was putting pressure on his spinal nerves and with the surgery, they were able to remove some of the pressure it caused.

"Hopefully they will keep him a few days and let him come home," Allen said.