South African Hennie Otto fired a 63 to take a four-shot lead heading into the final round of the Italian Open in Milan.

Otto, who started the day two behind leader Robert Karlsson, had a remarkable 11 birdies and just two bogeys to take control on a day of low scoring at the Castello di Tolcinasco Golf & Country Club.

Still seeking a first European Tour title and battling to regain full status, Otto will get a quick chance to erase the memory of losing a five-stroke lead in Madeira two months ago.

In contrast, Karlsson endured a frustrating day in near-perfect conditions, opening with an eagle at the par-five first but having little joy thereafter, claiming a solitary birdie on the back nine as Otto surged clear.

The South African was out in three under par but tore up the back nine, coming home in 30 with six birdies including three at final three holes, closing with a real crowd pleaser at the last from 30 feet.

Otto will be hoping the flat stick will be as kind to him on Sunday in what looks sure to come down to a putting contest.

Karlsson is tied for second with compatriot Chrisian Nilsson and Spaniard Alvaro Velasco, who both shot up the leaderboard with rounds of 64.

English duo Phillip Archer and Ross McGowan are a shot further back on -17 after carding rounds of 65 and 64 respectively.