COMMERCE CITY, Colo. (AP) Sluggish in the first half, the Americans needed some kind of catalyst.

So the team called on Jerome Kiesewetter and Jordan Morris, ending their nights off.

Kiesewetter sparked the offense with a goal and an assist in the second half, and the United States beat Panama 4-0 in CONCACAF Olympic qualifying on a rainy Tuesday.

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Already through to the semifinal round, the Americans didn't have much to play for and rested several of their starters. Scoreless at halftime, coach Andi Herzog turned to his bench for a lift, sending in Kiesewetter and Morris.

The U.S. caught a break early in the second half when Panama defender Fidel Escobar knocked in a crossing shot. Kiesewetter then scored about three minutes later and Morris right after that.

Luis Gil wrapped up the scoring by converting a penalty kick, helping the Americans advance out of Group A with a 3-0 record. Canada finished second.

''Overall, in the first half, Panama was not the better team, but created two or three chances,'' Herzog said. ''After halftime with three goals in 10 minutes, we showed them we're the better team.''

Next up for the U.S. is an important game Saturday in Sandy, Utah, where the semifinal winners automatically qualify for the Olympics in Rio de Janeiro next summer. The U.S., which failed to qualify for the 2012 London Olympics, will play Mexico or Honduras, which face each other Wednesday night with the winner taking over the top spot in Group B.

U.S. goalkeeper Ethan Horvath had a rather quiet game as a steady rain fell most of the evening. He probably needed it as well, since he's just arriving from his club team in Norway. Herzog had to all but beg Horvath's club to allow him to travel to the U.S. for qualifying.

It just so happens that Horvath is from nearby Highlands Ranch, Colorado.

''At the end, I can't make a decision if a player (will play) whether he's born here or not,'' Herzog said. ''For me, it was clear that when Ethan was coming and felt fine, I wanted to start him right away.''

Goalkeeper Elieser Powell kept Panama close in the first half with one splendid save after another, including one where he tipped a ball over the crossbar.

Still, the disparity in talent was evident.

''These players have a better future than they have a present,'' Panama coach Leonardo Pipino said through an interpreter. ''We have to work hard, the federation has to work hard, to have something for them to do, a place for them to go.

''If you look at the U.S. and Mexico start lists, you'll see players who play in the MLS, who play in Europe. ... The federation has to work internally to find a place for them to go so they can continue to progress.''

There was a scary moment for the Americans near the end of the first half, when midfielder Maki Tall was tackled hard from behind and had to be carried off the field on a stretcher. He returned a few minutes later, but didn't play in the second half.

Gboly Ariyibi sent the pass into the middle that hit off Escobar's leg and went into the goal to start the scoring spree.

With nothing really on the line in this contest, the U.S. gave goalkeeper Zack Steffen and defender Matt Miazga the night off. Midfielder Marc Pelosi didn't play after needing stitches in his shin following a hard tackle in the Cuba match last Saturday in Kansas City, Kansas.

''We were kind of slow in the first half. They put the pressure on us,'' Gil said. ''Second half we got things going and once one goal came, three goals came right after it.''