A man who spent nearly five hours trapped in a baler was airlifted to Melbourne on Tuesday morning.

The 30 year old man from Tongala was baling hay (at 10pm Monday night) when a blockage occurred in the round baler.

The man disengaged PTO and entered the baler to remove the blockage.

The doors suddenly closed on the man and he become stuck inside the baler, trapped by his lower legs.

At 2.40am on Tuesday morning, the man's wife realised he hadn't returned home and then noticed the tractor was sitting stationary in the paddock.

She discovered her trapped husband and emergency services were contacted immediately.

The man was extracted quickly and paramedics assessed the man for crush injuries to his legs.

The decision to call in the ambulance helicopter was made and he was flown to the Alfred Hospital directly.

WorkSafe investigations will continue.

It is believed good samaritan contractors donated their time to finish the baling.