Oxford fought back from a goal down to claim a third successive win by beating Plymouth 3-2 at Home Park.
Olamide Shodipo won and calmly converted an 82nd-minute penalty as United rallied from 1-0 behind to lead 3-1.
Two minutes later, Argyle sub Byron Moore earned a spot-kick, after being felled by Sam Long, which top-scorer Luke Jephcott powered into the top corner to ensure a tense finish.
Attacking defender Long had put Oxford 2-1 up after 74 minutes, finishing off a slick one-two with sub Sean Clare with a deft side-foot at the near post.
Josh Ruffels had cancelled out Panutche Camara’s 12th-minute opener in the 37th minute, getting the final touch in a goalmouth scramble as Argyle failed to clear James Henry’s soaring free-kick.
Camara first-timed Ryan Hardie’s left-wing cross into the roof of the net to put Argyle ahead.
Oxford then could have gone ahead in the 68th minute but home skipper Joe Edwards headed Rob Atkinson’s header off the line.
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