In Peskin & Schroeder's book page 524, the following diagram is calculated for the gauge boson self-energy in order $g^2$:
In dimensional regularization, its contribution is given by
At this point, Peskin & Schroeder say that "we could simply discard this diagram". It is clear that the integral over $p$ does not give a pole as $d\rightarrow 4$, but it is also divergent. Why can we simply discard this diagram? (Just because it is not logarithmically divergent?) Many thanks in advance!