(1) Assuming you are going to key the result as "3-0", the cell in which you type the result will need to be formatted as text.
(2) Lets say you are using Columd D for the result and starting at Row 6.
Choose a column over to the right, say 'M' to start your formulae.
In M6 insert formula If(

="3-0",5,0)
In N6 insert formula If(

="2-1",4,0)
In O6 insert formula If(

="1-2",1,0)
In P6 insert formula If(

="0-3",0,0) This one really redundant but included it anyway
Then in what ever cell you want the points tally displayed, assuming you want it on the same row as the match, insert formula =sum(M6:P6).
Copy down as required.