Key to correct blade angle at the top
The angle of the club-face (or blade) at the top is governed by the angle that the back of the left hand makes with the left forearm. At the top of the swing the left wrist should be slightly "cupped"
That is, the angle formed between the back of the left hand and the forearm should be about 30 degrees. This is ideal! This wrist position will place the club-face at the correct angle, namely (a) with the leading edge of the club VERTICAL or (b) inclined at an angle of about 30 degrees to the vertical ....or somewhere between these two. All other angle at the top are incorrect and will lead to inaccuracy and loss of power.
Here, the angle between the back of the left hand and the forearm is MUCH TOO PRONOUNCED.
the wrist is far too "cupped" and the club-face is consequently "open". I call this a "concave position" of the left wrist. It is extremely common among handicap golfers and tends to promote a slice