The Gunners beat Leicester 2-1 thanks to a late winner from Danny Welbeck.
Welbeck returned from a lengthy absence with a knee injury to head home one of his most important goals.
The win leaves Arsenal second in the table, just two points behind Leicester.
And Wenger claims the victory was a pivotal moment in his side's title hunt.
"It was a pivotal moment today because the mathematics meant it could be eight points or it could be two points. That is a great change," said Wenger.
"There's a long way to go, we play a lot of big teams. But we had a bad spell where we couldn't win for four games and have now won two on the bounce.
"We have come out of that bad spell and still have a good chance.
"It will strengthen our belief that we're in the fight. A loss today would have been massive."