PHOTOS: Portugal live to fight another day; Algeria thump Korea

Just when it looked as though the Americans had secured a come-from-behind victory to qualify for the second round, Silvestre Varela scored with a flying header from a Cristiano Ronaldo cross to keep alive Portugal's hopes.

Clint Dempsey had given the United States the lead in the 81st minute, steering the ball home with his stomach from close range.

But Varela's stoppage-time equaliser helped Portugal to secure a 2-2 draw in the Group G match at Manaus. 

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Nani scored in the fifth minute to give Portugal a 1-0 lead against the United States at halftime in their Group G match on Sunday, firing home from the edge of the six-yard box after a defensive error by Geoff Cameron.

The winger nearly doubled Portugal's lead in the 45th minute when he struck the post with a long-range shot. U.S. goalkeeper Tim Howard made a fine save from Eder's follow-up effort. 

However, having taken an early lead, Portugal then sat back in the heat and humidity, allowing the Americans to start dominating.

It was little surprise when midfielder Jermaine Jones cut in from the left in the 64th minute and fired in a superb right- foot curling shot from 25 metres to equalise.

Thereafter Dempsey put the Americans ahead before Varela saved Portugal's blushes.

The result means the U.S. are in second place, level with Germany on four points, and Portugal are third with one and face a tough task to make the next round.

In an earlier match, Algeria thrashed South Korea 4-2 in a Group H match at Estadio Beira-Rio in Porto Alegre.

Algeria led South Korea 3-0 at halftime after totally dominating their opponents in a half in which they also spurned several chances.

Algeria took the lead in the 26th minute when striker Islam Slimani ran on to a long upfield pass and held off two Korean defenders before guiding the ball past onrushing goalkeeper Kim Chang-soo.

The North Africans doubled their lead just two minutes later when Rafik Halliche headed home a corner from Abdelmoume Djabou and added a third in the 38th minute when a Slimani pass found Djabou inside the box and the attacking midfielder swept a left- foot shot into the corner of the net.

When Abdelmoumene Djabou got the third in the 38th minute, it marked only the third time in tournament history that an African side had scored three goals in the first half - after Algeria's effort against Chile in 1982 and Senegal's effort against Uruguay in 2002.

It's an unbelievable feat considering four years earlier, Algeria failed to trouble the scorers in South Africa.

Five minutes after the restart, Son Heung-Min pulled one back for Korea. However, in the 62nd minute Yacine Brahimi scored his first international goal to restore his side's three goal advantage, thereby making Algeria the first African side to score four times in a World Cup match.