Michael Coulson's disputed 48th-minute penalty brought the Minstermen a vital victory that lifted them above the U's and back into seventh place.
Worthington said: "It's a fantastic three points for us.
"The important thing was to keep a clean sheet and we've done that.
"What pleased me most about the performance was the way we showed a real togetherness within the group.
"Everybody within the group did a shift, and if you're going to be successful, that's what you need.
"It was a hard-fought game against a good Oxford side.
"Oxford started off very well. We withstood the early pressure and then came into the game. We managed the game very well."
The penalty, for a handball by Dave Kitson following a corner, was awarded in the end by a linesman, after referee Oliver Langford seemed ready to let play go on.
"What amazed me with the penalty was that the referee was standing right next to it and didn't give it," said Worthington.
"But his assistant did, and he was spot on, because I was 50 yards away and I thought it was a handball.
"And credit to Coulson, he stepped up and put it away."
York extended their unbeaten run in League Two to 14 games, and Worthington said: "We've got three games to go and we're ticking along nicely.
"It was a terrific win at the business and of the season."
Coulson converted the spot kick with aplomb, firing it high into the top-left corner to give U's keeper Ryan Clarke no chance, although he had dived the right way.