Suraj Roman attacked the driver - who agreed to give him a lift for free - five years ago and fled the country after the assault.
But he was arrested at Luton Airport in 2015 when returning to the UK and went on trial at Northampton Crown Court.
Detective Constable Andrew Scott, who led the investigation, said: "Within two days of committing this horrific attack, Roman tried to escape and went back to Romania.
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"He even changed his appearance and later tried to sneak back into the country.
"Despite the amount of time that passed, we managed to arrest him and have now successfully got a good result in court for the victim.
"This was a sustained attack, even as the victim was trying to get away, on an innocent man who offered him a free lift just out of his good nature.
"Roman repaid him with a violent outburst that will no doubt live with the victim for the rest of his life."
In September 2013, Roman had cold-called the victim at his home having noticed his taxi parked outside.
Initially, the victim had refused to give Roman a lift because he had admitted not having any money to pay for the fare.
Roman returned to the victim’s home and convinced his mum to persuade the victim to offer the lift without payment.
The victim agreed and drove Roman - of Craven Road, Rugby - 19 miles from Coventry to Berryfields Farm off the A45, between Braunston and Daventry.
It was at this point that Roman withdrew a screwdriver he had on him and started attacking the victim to the head.
The victim fled the car, followed by Roman, who tackled him and continued a vicious attack.
The victim eventually managed to escape and flag down a passing motorist who alerted police.
Officers later discovered that Roman had fled the country, but in 2015 he was arrested at Luton Airport.
Roman denied the offences, having changed his personal appearance, and went to trial at Northampton Crown Court.
DNA and fingerprint evidence connected Roman to the offence and following a three-day trial, he was found guilty of causing grievous bodily harm and sentenced to nine years imprisonment.