Leonardis Variation

2.d3

2. d3 is known as the Leonardis Variation. The Leonardis Variation is inferior to most other responses to the open game (like 2. Nf3 or 2. Bc4) because it is very passive and blocks off the light squared bishop (hems it to a defensive role on e2). Also, this is a very quiet move and allows black easy equality with 2... Nf6 followed by 3... d5. However, this can be taken as a reversed Philidor Defense, and in that case, it is quite playable for white (this still results in equal positions, but black has a small first-move advantage). Nevertheless, as told before, this move does effectively give up White's first move advantage to black, so is never played very commonly.