qgis - Join Point to the Nearest Polygon

I'm using QGis 2.18.3 on Windows 10.

I'm trying to join a point layer with a polygon layer. However, since it is a city grid map, points that do not fall within the polygons do not get joined.

My expectation was that QGis could join those points to the nearest polygon.

Can somebody help me with that?

Here's a picture of my map.