Q:

Leaflet map "center" option not working

I have a map and I want to center it to concrete point.  Following implementation is working correctly:
 var map = L.map('map', {
                crs: crs
            }
    );

 map.setView([58.66, 25.05], 2);

However, implementation below is not working correctly and does not center the map.  Why it is happening?  I get just blank grey area instead of my map.   According to the documentation it does completely the same as the code above. 
  var map = L.map('map', {
                    crs: crs,
                    center: L.latLng(58.66, 25.05)
                }
        );
    map.setZoom(2);

Why? 

A:

I think if you specify the center option when creating the map you also have to specify the zoom option or leaflet doesn't know what tiles to request. 
var map = L.map('map', {
    center: L.latLng(58.66, 25.05),
    zoom: 2
});

When you use setView, you are setting center and zoom so leaflet knows the tiles to request.