ROTHERHAM United's three-match winning run came to an end at hands of League One form's team at AESSEAL New York Stadium.
The Millers were beaten 2-1 by an Oxford United side who extended their own unbeaten streak to nine matches.
There was all to play for at half-time when the score was 1-1 but the home team suffered a frustrating second period and fell to a 57th-minute winner.
Paul Warne's men mustered only one effort on target after the break and defeat dropped them a place in the table to 11th.
All four sides of New York rose for a minute's applause in the 16th minute to remember Millers fan Charlie Louise Hunter who died earlier this month aged just 16.
On the pitch, Oxford took a 23rd-minute lead when Cameron Brannagan dispossesed Matt Olosunde and Tariqe Fosu-Henry fired home from the edge of the area.
Rotherham shouts for handball were rejected when Jake Hastie's shot was kept out close to the goalline by Chris Cadden before Dan Iversen saved from Brannagan at the other end and John Mousinho headed over.
The Millers were level after 35 minutes when Michael Ihiekwe drove deep into Oxford territory and fed Michael Smith. The man who had started the move so well was there to head home, latching on to Matt Crooks' headed flick as Smith's cross came in from the right.
The home side fell behind again 12 minutes after the break when Matt Taylor headed home Brannagan's cross at the back post and didn't really threaten an equaliser until the dying mnutes.
They were second best to the U's, whose niggling and shirt-pulling was allowed to go unchecked by referee Scott Oldham.
After Jamie Lindsay had superbly foiled James Henry in the act of shooting, Iversen had to be at his best to deny Taylor a second before a Mousinho effort was deflected over.
Supporters from both sides applauded again, in the 66th minute, this time in memory of Oxford follower Andy 'Womble' James.
Rotherham almost stole an equaliser in added time when Olosunde's cross took a deflection from Cadden and forced Simon Eastwood into a vital save at his near post.
Fosu-Henry nearly scored a last-gasp third for Oxford who looked more of a play-off team than the Millers.
Rotherham (4-4-1-1): Dan Iversen; Matt Olosunde, Michael Ihiekwe, Richard Wood, Joe Mattock; Ben Wiles, Jamie Lindsay, Dan Barlaser (Chiedozie Ogbene 66), Jake Hastie (Julien Lamy 77); Matt Crooks (Carlton Morris 72); Michael Smith. Subs not used: Lewis Price, Billy Jones, Trevor Clarke, Shaun MacDonald.
Oxford (4-1-2-3): Simon Eastwood; Chris Cadden, Elliott Moore, John Mousinho, Josh Ruffels; Alex Rodgriguez-Gorrin; James Henry (Sam Long 90+1), Cameron Brannagan; Mark Sykes (Shandon Baptiste 74), Matt Taylor (Jamie Mackie 86), Tariqe Fosu-Henry. Subs not used: Jack Stevens, Robert Hall, Daniel Agyei, Nico Jones.
Goals: Ihiekwe 35 (Rotherham); Fosu-Henry 23, Taylor 57 (Oxford).
Referee: Scott Oldham (Lancashire).
Attendance: 8,837 (734).