Lagging Rebus #535

If your new to Rebuses, you can read how to solve a Rebus here (link opens in a new window).
 
Do you need a little help? Click to reveal a clue to the above Rebus.
Here is clue to help decipher the hidden meaning. To fall behind someone or something.

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Do you think you have got it? Click to view the answer.
The word “Lagging” is backwards, to give the answer: Lagging Behind.
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