Oxford ended Shrewsbury's 100 per cent run by holding them to a 1-1 draw at the Kassam Stadum.
Gino van Kessel fired the U's in front on 75 minutes, shooting in off a post after Junior Brown had cleared off the line at a corner.
But the Shrews levelled on 84 minutes when substitute Stefan Payne found space in the box at a similar scramble following a corner that was not properly cleared.
The Shrews showed invention from a free-kick when Shaun Whalley chipped over the wall for Jon Nolan, whose drive was saved low at his near post by Simon Eastwood.
Oxford, second best in the first half, improved when Jon Obika and Joe Rothwell came on after an hour, and the former immediately tested Dean Henderson with a drive that the keeper palmed aside.
Shrewsbury striker Carlton Morris was unlucky as he lobbed over Eastwood, only to see it hit the bar and bounce down on the goal-line, without going over.
Payne then missed a great opportunity to win it for Shrews in stoppage time.