 If White wants to avoid this variation, he must play either 4. e4 (Marshall Gambit) or 4. e3 (which usually transposes to the Meran, but deprives White of the Bg5 variations).White now has a number of possible continuations, including 5. a4 (see below), 5. e3 (often transposing to the line given below), 5. e4 (with similarities to the line given below), or even 5.Bg5.