Mitchell, who plays with the Commonwealth Golf Club in Melbourne, claimed both the under 18 Western District Golf Association championship and the Sungold Open.
He says it was a great thrill when his final put rolled in.
In the women's tournament, Colac's Georgia Fish followed on from her success in the Port Fairy tournament on Sunday to take out her second consecutive Sungold Open.
Georgia had rounds of 80 and 81 to win by three shots.
The 17 year old said she was thrilled to win two years in a row given the conditions over the two days were very challenging.