Earlier, Curacao scored a very late equaliser to draw 1-1 with Jamaica in the early game in Group C.
Jamaica ended up topping the group with five points, followed by Curacao and El Salvador on four each. Curacao, however, advanced with a better goal difference.
El Salvador kicked off against Honduras knowing that with a win they would top the group, while a draw would also assure a quarter-finals berth.
But they were knocked on their heels in the 59th minute when Honduras midfielder Jorge Alvarez curled a delicious 23-yard shot inside the post.
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It was 2-0 six minutes later when Rubilio Castillo calmly finished after being put through by Luis Garrido.
Bryan Acosta delivered the knockout blow in the 75th minute after latching onto a pinpoint 50-yard long ball by defender Maynor Figueroa.
Emilio Izaguirre completed the rout in the 90th minute.
(Reporting by Andrew Both in Cary, North Carolina; editing by Sudipto Ganguly)
