The US were staring almost certain elimination in the face when 2-0 down at halftime and their battling comeback in one of the tournament's most pulsating encounters kept alive their hopes of progress to the last 16.
Slovenia were eight minutes away from becoming the first team to qualify for the knockout stage after well-taken goals from Valter Birsa in the 13th minute and Zlatan Ljubijankic in the 42nd.
But Landon Donovan scored a brilliant individual goal three minutes after the break and as the Americans poured forward, Michael Bradley, son of coach Bob Bradley, grabbed an equalizer eight minutes from time.
Slovenia lead Group C with four points from the US on two. England, with one point so far, play Algeria, with none, later in Cape Town.
There was rare anger and bitterness though from the normally reserved US team after a Maurice Edu effort five minutes from the end was ruled out for a far from clear infringement.
Donovan swung in a free kick from right into the crowded Slovenia area and Edu met the cross to fire home but referee Koman Coulibaly of Mali whistled for what presumably was pushing inside the area.
US players protested furiously and were left fuming at the decision after the game — Michael Bradley shouting in the referee's face at the finish.
"I am a little bit gutted to be honest. I don't know how they stole that third goal from us. It's too bad because that was a fair goal I think," Donovan said.
"I saw a good finish and a good goal. I'm not sure what the call was, he wouldn't tell us what the call was."
The controversy should not however overshadow what was a game full of passion and positive endeavor from both sides.
Slovenia grabbed the lead through a superb 25 meter strike from Valter Birsa — left in acres of space the winger looked up and fired past a strangely stationary Tim Howard to prompt a choreographed celebration from the Slovenes.
The U.S were chasing shadows at time in midfield with Birsa causing isolated U.S left-back Carlos Bocanegra all kinds of trouble.
After a rare spell of pressure from the US, Slovenia pounced on the counter-attack — Milivoje Novakovic split open a flat back line with a superb through ball to Zlatan Ljubijankic who kept his cool and slotted past the advancing Howard.
US coach Bradley had plenty to sort out at the break and he brought on Edu and Benny Feilhaber to the midfield, taking off the ineffectual Jose Torres and striker Robbie Findley.
Within three minutes of the restart the US pulled a goal back, Donovan cutting in from the right flank and then blasting in at the near post from the tightest of angles with a shot of terrific power.
The US poured forward in search of an equalizer and eight minutes from time Bradley surged into the Slovenia penalty area to get onto a knock-down from Jozy Altidore and put a rising shot past Slovenia keeper Samir Handanovic.
Then came the controversy.
US coach Bradley was careful with his words but was clearly non-plussed by the decision.
"We still don't know why the goal was disallowed...Noone knows. It is important to understand that the players put a lot of emotion into the game and now they want a fair outcome," coach Bradley said.
