The Saddlers host Karl Robinson’s side at the Banks’s Stadium tomorrow knowing they have just six games left to save their League One status.
Just a few weeks ago, The U’s were sat in the bottom four but a run of three straight wins has propelled them up to 12th in the table.
Walsall – in contrast – have lost their last four and are now sit in the drop zone.
But the incredible atmosphere generated in the win against Northampton helped the Saddlers survive last season.
And Keates wants fans to recreate that tomorrow.
“The fans’ support, more than ever, is going to be needed over the next six games,” he said.
“We need them for Oxford. The Barnsley atmosphere in the last game was unbelievable. They helped the team get on the front.
“Last year it came down to that Northampton game and the volume from the fans was unbelievable.
“The atmosphere and what happened in the last few minutes is something I will always look back on with fond memories.
“That atmosphere needs to be recreated. There have been points over the season where the fans have done that and we need it again now.
“We need to be united and we need to make sure we get what we need at the weekend so we can get out the relegation zone.”
With his team sat in the relegation zone, Keates knows he is under pressure to get results.
“We are losing games and we are in a results business,” he continued.
“I don’t want to be in charge of a football club that is down there.
“I came in last season and the objective was to stay up.
“The aim this season was to get us in a positive position and we are not in a positive position at the moment so there is pressure on that.
“The aim is to get something on the board against Oxford and start looking forward.”
Meanwhile, Oxford were yesterday served with a winding-up petition from Kassam Stadium landlords Firoka.
A hearing has now been set for May 22.
It is believed the petition relates to the latest rent payment, which was due last month, and comes days after the club paid their non-playing staff late for March.