The U.S 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 reaching the second round.
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 forwards, Michael Bradley, son of coach Bob Bradley, grabbed an equaliser eight minutes from time.
Slovenia lead Group C with four points from the U.S. on two. England, with one point so far, play Algeria, with none, later in Cape Town.
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There was rare anger and bitterness, though, from the normally reserved U.S team after a Maurice Edu effort five minutes from time was ruled out for an infringement.
Donovan swung in a free kick from right into the crowded box and Edu met the cross and fired home but referee Koman Coulibaly of Mali whistled presumably for pushing in the area.
AMERICANS FUMING
U.S. 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 metre 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 chased shadows at times in midfield with Birsa causing isolated left-back Carlos Bocanegra all kinds of trouble.
After a rare spell of pressure from the U.S, 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.
U.S coach Bradley had plenty to sort out at the break and he brought on Edu and Benny Feilhaber in midfield, taking off the ineffectual Jose Torres and
