Intro: Em
Verse: Em | G | D/F#
Chorus 1: C | Em (x3) | C | Am
Chorus 2: C | Em (x3) | C | Am | D
Instrumental: Em | D/F# | G
I fiddled around until I found a way to play it that fits roughly with this version he did: 
:)

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Intro: Em x3


     Em                   G       D/F#
That old dog knows how to find me 
   Em                             G    D/F#
It matters not which road I travel on 
      Em                      G          D/F#
And I thought those days were behind me 
       Em                                 G        D/F#
But it turns out I could not have been more wrong 
       Em                     G        D/F#
And he sits right there on my shoulder 
     Em                      G     D/F#
His cold, wet breath upon my neck 
        Em                             G       D/F#
And they said he would leave when I got older 
       Em                             G     D/F#
But he still creeps up when I least expect 

         C                  Em
And it's hard to say why it has to be today 
      C                    Em
And I can't explain how it feels 
      C                      Em
But a black dog day could be just one sleep away 
         C                                  Am                              Em
And I'll never see him coming but I'll keep running with him snapping at my heels 


            Em                      G      D/F#
And there's no good reason for his visits 
      Em                         G      D/F#
He requires neither catalyst nor cause 
          Em                  G      D/F#
And he'll push me to my very limits 
        Em                                G      D/F#
Leaving nothing but the scars left by his claws 
       Em                            G     D/F#
And he steals the wind right out my sails 
       Em                            G      D/F#
And he leaves me at the mercy of the waves 
          Em                G         D/F#
And I've tried but I have failed to outrun him 
            Em                          G      D/F#
But I'm not fast enough on my feet to escape 


         C                  Em
And it's hard to say why it has to be today 
      C                    Em
And I can't explain how it feels 
      C                      Em
But a black dog day could be just one sleep away 
         C                                  Am                              D
And I'll never see him coming but I'll keep running with him snapping at my heels 
      Em     Em D/F#      D/F# G      G D/F#    (switch quickly between the ones that are closer together)
At my heels 


D/F#    C                   Em  
And it's hard to say why it has to be today 
      C                    Em
And I can't explain how it feels 
      C                      Em
But a black dog day could be just one sleep away 
         C                                  Am                              D
And I'll never see him coming but I'll keep running with him snapping at my heels 
         C                  Em
And it's hard to say why it has to be today 
      C                    Em
And I can't explain how it feels 
      C                      Em
But a black dog day could be just one sleep away 
         C                                  Am                              Em
And I'll never see him coming but I'll keep running with him snapping at my heels