The following simulates removing a colorcast by converting to LAB mode and then using curves on the AB channels. However, you can use this method without leaving the original color mode.
It’s another quick-and-dirty method for removing a colorcast. After opening the document, take the following steps:

1. Select the Eyedropper tool and set its options to Size Sample 3 by 3 Average.

2. Drag the Eyedropper tool over the color you want to remove.

3. Make a new layer and fill it with the color that you just sampled (Edit>Fill>Use: Foreground Color).

4. Choose Image➜Adjustments➜Invert, or use the keyboard shortcut of Ctrl+I(Windows),Ô+I (Mac OS).

5. Change the layer’s blend mode to Color.

6. Lower the opacity of the layer to 50%.
That should get you into the ballpark. At step 2, you can also try duplicating the image layer, running the BlurâžœAverage filter and inverting the layer.

Before and after applying Auto Color

TIP: Where appropriate, try to set neutral end points first by using the eyedroppers in Curves or Levels.