Tiger Woods could face potential disqualification from the Masters after an illegal drop shot.

Woods shot on the par five 15th hole struck the pin before spinning back into the water.

The World No 1 decided against playing from the drop zone and went back to the original spot where he struck his third shot of the hole.

But by his own admission he moved the ball two yards further back than its original starting point.

That is illegal according to USPGA rules and would normally result in a two shot penalty had Woods' not signed his scorecard. He is currently on 3 under par.

With his scorecard signed and sealed, disqualification is a possibility.

But Tiger may escape punishment, although 14-year-old Chinese amateur Tianlang Guan was penalised for slow play during yesterday's round.