Error opening Partial's in a new tab from a function in javascript

I have the following case: I have a "Third Party" navigation page, with several Partials that defines its corresponding data.

To do this navigation I'm doing it by javascript , and I load Partial as follows (example of a partial):

$("#divContactosTerceiro").empty();
$("#divContactosTerceiro").load("Terceiros/sContactosTerceiro", { NumRegistoTerceiro: result.result.NumRegisto });

Here I send the data NumRegistoTerceiro to the controller Terceiros/sContactosTerceiro . So far so good, it works perfectly.

What am I doing now? I'm opening in a new tab from a page of Alertas , the page of Terceiros , where it will execute the javascript function of the code example above.

Problem? It is that javascript adds twice the name of the controller to load Partial on the new tab, as shown in the image:

How can I get around this problem? I can not find any useful reference on the net.