Referencing Worksheet from A Cell

Is this possible?

I have a name of a worksheet in column K.

Below is a sippet of my code. If I change the part Ptr, "K" to an an actual name of a worksheet the code runs. However, I have the name of a sheet in the cell Ptr, "K" and it doesn't run.

Please help. Thanks!

Next Ptr
    If Not RangeToCut Is Nothing Then
        With RangeToCut.EntireRow
            targetRow = Worksheets(Ptr, "K").Cells(Rows.count, "a").End(xlUp).Row

But this code works...

Next Ptr
    If Not RangeToCut Is Nothing Then
        With RangeToCut.EntireRow
            targetRow = Worksheets("Monday").Cells(Rows.count, "a").End(xlUp).Row