search & replace macro

Hi, I'm using search & replace in a macro but only want to replace the text if it is in the first 3 letters within the cell. So, for example, I currently have;

Selection.Replace What:="DS", Replacement:="", LookAt:=xlPart, _
        SearchOrder:=xlByRows, MatchCase:=False, SearchFormat:=False, _
        ReplaceFormat:=False

This is to delete the text "DS" but obviously it's deleting DS anywhere within the text rather than just at the beginning of the text.

any help much appreciated.

Liam