Things remain tight at the foot of the League Two table as ten man Carlisle eventually succumbed to the pressure and gave way to a fantastic strike from Oxford debutant Kyle Vassell.
Oxford should have been ahead with just three minutes on the clock when Grainger and Brough combined to stop Hylton in full flight. The ball broke free and a low cross from Rose found Hoban unmarked and just six yards out. He completely missed his first attempt to make a connection but it sat up nicely and Hanford was relieved to see the second volley rebound off his shin and away to safety.
The U's kept the pressure up and Mullins drilled a low volley right at Hanford when he waited for it to drop out of the air on the edge of the area. Hylton was then stopped from going one on one by a timely challenge from Brough as Carlisle struggled to get a foothold in the game.
United weathered the storm and grabbed the lead when a wind assisted 40-yard free kick from Corry was allowed to curl deep. Clarke stayed on his line and he was left to rue the decision as it skipped up off the surface and into the back of the net via the underside of the bar.
Oxford tried to put the early blow behind them with a flowing move which left Rose with a clear sight of goal. His rasping drive took a touch off Young and ricocheted away to safety as it rattled back off the woodwork.
Carlisle had to keep their concentration, with blocks from Grainger and Kennedy setting the tone, and they picked their moments to attack with Rigg going close when Wyke nodded a Young throw onto his boot. His volley beat Clarke but it was always going wide.
Trickery from Wyke temporarily opened things up as he broke from deep, but his pull back for Kennedy brought a sliding tackle from Mullins which stopped the shot at source.
The Oxford equaliser came from a moment of skill from Roofe when he shrugged off close attentions from Monakana to deliver a wonderful near post cross with the outside of his boot. Patrick Hoban made the near post run and he was able to celebrate his first goal for the U's when he glanced a powerful header into the roof of the net.
The same players combined moments later, as the U's increased the pressure ahead of the break, but Grainger held his position and got in the way as the striker let one fly on the spin.
The hosts kept probing at the start of the second half and Baldock beat two to test Hanford from distance as the home crowd urged their side to pick up the pace. Hylton then carried the ball down the left flank and across the face of the 18 yard box before bringing a full length save out of Hanford as he tried to tuck it into the bottom corner.
Strong work from Wyke led to a neat through ball for substitute Derek Asamoah to chase but he had to shoot on the stretch from a tight angle. Clarke spread himself and pulled it close to his chest.
Archibald-Henville received his marching orders when he was booked twice in the space of two minutes as Oxford used the conditions to peg Carlisle back, and Rigg and Hanford both made goal line clearances in the wake of the dismissal as the high balls continued to rain in.
The persistence was eventually made to pay when substitute Kyle Vassell marked his home debut with a stunning strike on the half volley which fizzed into the bottom corner.
Baldock smashed the post with a close range header as Oxford tried to extend their lead, and Hanford denied Roofe with a wonder save deep into time added on as the action remained mostly in the visiting half.
Oxford - Hoban (38), Vassell (80)
United - Corry (9)
Oxford - Baldock (53)
United - Archibald-Henville (66 & 68 - sent off), Corry (77)
Oxford United - Clarke, Skarz, Mullins, Wright, Rose (O'Dowda 86), Hoban (Vassell 75), Hylton (Roberts 90), Baldock, Ruffels, Collins, Roofe. Subs - Ashdown, Whing, Long, Dunkley.
Carlisle United - Hanford, Young, Archibald-Henville, Grainger, Brough, Dempsey (Atkinson 76), Kennedy, Corry, Monakana (Asamoah 54), Rigg, Wyke (Buddle 70). Subs - Gillespie, Paynter, Kearns, Beck.
Referee - Mr Gavin Ward
Attendance - 5,515 (476 away fans)