Argyle 0-2 Barnet
Argyle suffered their second home defeat in four days as their lead at the top of League Two shortened.
First-half goals by Bira Dembele and John Akinde saw off the Pilgrims, who were well below their best for the second game in a row.
Argyle dominated possession and threatened occasionally, with David Fox hitting the bar, but they failed to find the net.
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