How do I insert a model into a backbone.js collection in a specific index?

I need to insert a model into a Collection at position Collection.length-2. The last model in the collection should always stay the last model in the collection. What I tried so far: I added one "page" model to the Collection "Pages" and then tried to swap them around by changing their sequence: ``` var insertedpage = Pages.at(Pages.length-1); var lastpage = Pages.at(Pages.length-2); insertedpage.set({sequence: Pages.length-1}); lastpage.set({sequence: Pages.length}); ``` I also tried to remove the last page, then add a new page and then add the last page back in. ``` var lastpage = Pages.pop(); Pages.add({example1: example2}); Pages.push(lastpage); ``` neither of these worked. The newly added page still appears as last model in the Collection. Do I need to call some kind of order function after this?