After a 2-1 defeat at Concord Rangers, City are two points above the bottom three places but have played more games than most of the teams below them, writes Tom Feaheny.
"It was frustrating, we were so desperate to do well and it has just not happened, we have got a mistake in us," Jones told BBC Radio Oxford.
"We controlled possession and we give it away and they score a wonderful goal.
"We looked to be on the front foot but we looked like we could concede one on the break, but we have a bit of a soft underbelly at times."
"The group is in a relegation battle and now we have to get together and fight to stay in this league."
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