Sean Johnson pulled off a handful of electric stops to allow his team's early and late goals to stand up in the win.
Patrick Nyarko picked off a wayward pass on the halfway line just a few seconds into the match and bore down on goal. He nutmegged Tally Hall to give the Fire a blazing hot start.
Mac Kandji put the ball in the back of the net a dozen minutes later. Sean Johnson, on the day he was called up to the U.S. national team roster to play Jamaica in a World Cup qualifier in Kingston, made a hash of Andre Hainault's cross, batting it into Kandji. The ball bounced off what looked like Kandji's shoulder and into the net, with the referee belatedly ruling out the goal.
Instead, the Fire doubled their lead, again thanks to a poor pass in the Dynamo midfield. This time Alvaro Fernandez snapped up possession and fed Sherjill MacDonald, who held up the ball before shooting. Daniel Paladini capped up a late run into the box by connecting with the scuffed attempt to finish it.
Johnson went out of his way to show that Jurgen Klinsmann's faith is justified, pulling off five saves to maintain Chicago's lead. Still, he could do nothing about Brian Ching's deflected header from a corner kick in the final minute of regular time.
Alex scored a long-range blast deep in injury time to cap the win.
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