Convert String to latlng google maps

I want to convert a String with a pattern like "(53.324523, 43.252352)" into a latlng. I already found the right function:

var input = latlngArray[i];
var latlngStr = input.split(",",2);
var lat = parseFloat(latlngStr[0]);
var lng = parseFloat(latlngStr[1]);
latlngArray[i] = new google.maps.LatLng(lat, lng);

The problem is that I can't get a proper lat. When I use alert to display it it only says NaN, while the lng variable displays the right value.

Got it. Thx for the help.

var input = latlngArray[i].substring(1, latlngArray[i].length-1);
var latlngStr = input.split(",",2);
var lat = parseFloat(latlngStr[0]);
var lng = parseFloat(latlngStr[1]);
latlngArray[i] = new google.maps.LatLng(lat, lng);